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diff --git a/docs-xml/Samba3-HOWTO/TOSHARG-CUPS-printing.xml b/docs-xml/Samba3-HOWTO/TOSHARG-CUPS-printing.xml new file mode 100644 index 00000000000..9b12e4cac59 --- /dev/null +++ b/docs-xml/Samba3-HOWTO/TOSHARG-CUPS-printing.xml @@ -0,0 +1,5237 @@ +<?xml version="1.0" encoding="iso-8859-1"?> +<!DOCTYPE chapter PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc"> +<chapter id="CUPS-printing"> + +<chapterinfo> + + <author> + <firstname>Kurt</firstname><surname>Pfeifle</surname> + <affiliation> + <orgname>Danka Deutschland GmbH </orgname> + <address><email>kpfeifle@danka.de</email></address> + </affiliation> + </author> + <author> + <firstname>Ciprian</firstname><surname>Vizitiu</surname> + <affiliation> + <address><email>CVizitiu@gbif.org</email></address> + </affiliation> + <contrib>drawings</contrib> + </author> + + <author>&person.jelmer;<contrib>drawings</contrib></author> + + <pubdate> (27 Jan 2004) </pubdate> +</chapterinfo> + +<title>CUPS Printing Support</title> + +<sect1> + + <title>Introduction</title> + + <sect2> + <title>Features and Benefits</title> + + <para> +<indexterm><primary>default printing</primary></indexterm> + The Common UNIX Print System (<ulink url="http://www.cups.org/">CUPS</ulink>) + has become quite popular. All major Linux distributions now ship it as their default printing + system. To many, it is still a mystical tool. Mostly, it just works. People tend to regard + it as a <quote>black box</quote> that they do not want to look into as long as it works. But once + there is a little problem, they have trouble finding out where to start debugging it. Refer to + <link linkend="classicalprinting">Classical Printing</link>, which contains much information + that is also relevant to CUPS. + </para> + + <para> +<indexterm><primary>CUPS</primary></indexterm> + CUPS sports quite a few unique and powerful features. While its basic functions may be grasped quite + easily, they are also new. Because it is different from other, more traditional printing systems, it is best + not to try to apply any prior knowledge about printing to this new system. Rather, try to understand CUPS from + the beginning. This documentation will lead you to a complete understanding of CUPS. Let's start with the most + basic things first. + </para> + + </sect2> + + <sect2> + <title>Overview</title> + + <para> +<indexterm><primary>print spooling system</primary></indexterm> +<indexterm><primary>CUPS</primary></indexterm> +<indexterm><primary>printer management system</primary></indexterm> +<indexterm><primary>IETF</primary></indexterm> +<indexterm><primary>Internet Printing Protocol</primary><see>IPP</see></indexterm> +<indexterm><primary>Internet Engineering Task Force</primary><see>IETF</see></indexterm> +<indexterm><primary>GUI</primary></indexterm> +<indexterm><primary>KDEPrint</primary></indexterm> + CUPS is more than just a print spooling system. It is a complete printer management system that + complies with the new Internet Printing Protocol (IPP). IPP is an industry and Internet Engineering Task Force + (IETF) standard for network printing. Many of its functions can be managed remotely (or locally) via a Web + browser (giving you platform-independent access to the CUPS print server). Additionally, it has the + traditional command line and several more modern GUI interfaces (GUI interfaces developed by third parties, + like KDE's overwhelming <ulink url="http://printing.kde.org/">KDEPrint</ulink>). + </para> + + <para> +<indexterm><primary>raw printers</primary></indexterm> +<indexterm><primary>smart printers</primary></indexterm> + CUPS allows creation of <emphasis>raw</emphasis> printers (i.e., no print file format translation) as + well as <emphasis>smart</emphasis> printers (i.e., CUPS does file format conversion as required for the + printer). In many ways, this gives CUPS capabilities similar to the MS Windows print monitoring system. Of + course, if you are a CUPS advocate, you would argue that CUPS is better! In any case, let us now explore how + to configure CUPS for interfacing with MS Windows print clients via Samba. + </para> + + </sect2> + +</sect1> + +<sect1> + <title>Basic CUPS Support Configuration</title> + + <para> +<indexterm><primary>CUPS</primary></indexterm> +<indexterm><primary>cupsd.conf</primary></indexterm> +<indexterm><primary>/etc/printcap</primary></indexterm> +<indexterm><primary>Printcap</primary></indexterm> +<indexterm><primary>PrintcapFormat</primary></indexterm> +Printing with CUPS in the most basic &smb.conf; setup in Samba-3.0 (as was true for 2.2.x) requires just two +parameters: <smbconfoption name="printing">cups</smbconfoption> and <smbconfoption +name="printcap">cups</smbconfoption>. CUPS does not need a printcap file. However, the +<filename>cupsd.conf</filename> configuration file knows of two related directives that control how such a +file will be automatically created and maintained by CUPS for the convenience of third-party applications +(example: <parameter>Printcap /etc/printcap</parameter> and <parameter>PrintcapFormat BSD</parameter>). +Legacy programs often require the existence of a printcap file containing printer names or they will refuse to +print. Make sure CUPS is set to generate and maintain a printcap file. For details, see <command>man +cupsd.conf</command> and other CUPS-related documentation, like the wealth of documents regarding the CUPS +server itself available from the <ulink noescape="1" +url="http://localhost:631/documentation.html">CUPS</ulink> web site. + </para> + + <sect2> + <title>Linking smbd with libcups.so</title> + + <para> +<indexterm><primary>libcups.so</primary></indexterm> + Samba has a special relationship to CUPS. Samba can be compiled with CUPS library support. + Most recent installations have this support enabled. By default, CUPS linking is compiled + into smbd and other Samba binaries. Of course, you can use CUPS even + if Samba is not linked against <filename>libcups.so</filename> &smbmdash; but + there are some differences in required or supported configuration. + </para> + + <para> +<indexterm><primary>libcups</primary></indexterm> +<indexterm><primary>ldd</primary></indexterm> + When Samba is compiled and linked with <filename>libcups</filename>, <smbconfoption name="printcap">cups</smbconfoption> + uses the CUPS API to list printers, submit jobs, query queues, and so on. Otherwise it maps to the System V + commands with an additional <command>-oraw</command> option for printing. On a Linux + system, you can use the <command>ldd</command> utility to find out if smbd has been linked with the + libcups library (<command>ldd</command> may not be present on other OS platforms, or its function may be embodied + by a different command): +<screen> +&rootprompt;<userinput>ldd `which smbd`</userinput> +libssl.so.0.9.6 => /usr/lib/libssl.so.0.9.6 (0x4002d000) +libcrypto.so.0.9.6 => /usr/lib/libcrypto.so.0.9.6 (0x4005a000) +libcups.so.2 => /usr/lib/libcups.so.2 (0x40123000) +[....] +</screen> + </para> + + <para> +<indexterm><primary>libcups.so.2</primary></indexterm> + The line <computeroutput>libcups.so.2 => /usr/lib/libcups.so.2 (0x40123000)</computeroutput> shows + there is CUPS support compiled into this version of Samba. If this is the case, and printing = cups + is set, then <emphasis>any otherwise manually set print command in &smb.conf; is ignored</emphasis>. + This is an important point to remember! + </para> + + <tip><para> Should it be necessary, for any reason, to set your own print commands, you can do this by setting + <smbconfoption name="printing">sysv</smbconfoption>. However, you will lose all the benefits + of tight CUPS-Samba integration. When you do this, you must manually configure the printing system commands + (most important: + <smbconfoption name="print command"/>; other commands are + <smbconfoption name="lppause command"/>, + <smbconfoption name="lpresume command"/>, + <smbconfoption name="lpq command"/>, + <smbconfoption name="lprm command"/>, + <smbconfoption name="queuepause command"/> and + <smbconfoption name="queue resume command"/>). + </para></tip> + + </sect2> + + <sect2> + <title>Simple &smb.conf; Settings for CUPS</title> + + <para> + To summarize, <link linkend="cups-exam-simple">the Simplest Printing-Related + &smb.conf; file</link> shows the simplest printing-related setup for &smb.conf; to + enable basic CUPS support: + </para> + + <example id="cups-exam-simple"> + <title>Simplest Printing-Related smb.conf</title> + <smbconfblock> + <smbconfsection name="[global]"/> + <smbconfoption name="load printers">yes</smbconfoption> + <smbconfoption name="printing">cups</smbconfoption> + <smbconfoption name="printcap name">cups</smbconfoption> + + <smbconfsection name="[printers]"/> + <smbconfoption name="comment">All Printers</smbconfoption> + <smbconfoption name="path">/var/spool/samba</smbconfoption> + <smbconfoption name="browseable">no</smbconfoption> + <smbconfoption name="public">yes</smbconfoption> + <smbconfoption name="guest ok">yes</smbconfoption> + <smbconfoption name="writable">no</smbconfoption> + <smbconfoption name="printable">yes</smbconfoption> + <smbconfoption name="printer admin">root, @ntadmins</smbconfoption> + </smbconfblock> + </example> + + <para> +<indexterm><primary>PDF</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>printer driver</primary></indexterm> + This is all you need for basic printing setup for CUPS. It will print all graphic, text, PDF, and PostScript + files submitted from Windows clients. However, most of your Windows users would not know how to send these + kinds of files to print without opening a GUI application. Windows clients tend to have local printer drivers + installed, and the GUI application's print buttons start a printer driver. Your users also rarely send files + from the command line. Unlike UNIX clients, they rarely submit graphic, text, or PDF formatted files directly + to the spooler. They nearly exclusively print from GUI applications with a <quote>printer driver</quote> + hooked between the application's native format and the print data stream. If the backend printer is not a + PostScript device, the print data stream is <quote>binary,</quote> sensible only for the target printer. Read + on to learn what problem this may cause and how to avoid it. + </para> + + </sect2> + + <sect2> + <title>More Complex CUPS &smb.conf; Settings</title> + + <para> + <link linkend="overridesettings">The Overriding Global CUPS Settings for One Printer example</link> + is a slightly more complex printing-related setup for &smb.conf;. It enables general CUPS printing + support for all printers, but defines one printer share, which is set up differently. + </para> + + <example id="overridesettings"> + <title>Overriding Global CUPS Settings for One Printer</title> + <smbconfblock> + <smbconfsection name="[global]"/> + <smbconfoption name="printing">cups</smbconfoption> + <smbconfoption name="printcap name">cups</smbconfoption> + <smbconfoption name="load printers">yes</smbconfoption> + + <smbconfsection name="[printers]"/> + <smbconfoption name="comment">All Printers</smbconfoption> + <smbconfoption name="path">/var/spool/samba</smbconfoption> + <smbconfoption name="public">yes</smbconfoption> + <smbconfoption name="guest ok">yes</smbconfoption> + <smbconfoption name="writable">no</smbconfoption> + <smbconfoption name="printable">yes</smbconfoption> + <smbconfoption name="printer admin">root, @ntadmins</smbconfoption> + + <smbconfsection name="[special_printer]"/> + <smbconfoption name="comment">A special printer with his own settings</smbconfoption> + <smbconfoption name="path">/var/spool/samba-special</smbconfoption> + <smbconfoption name="printing">sysv</smbconfoption> + <smbconfoption name="printcap">lpstat</smbconfoption> + <smbconfoption name="print command">echo "NEW: `date`: printfile %f" >> /tmp/smbprn.log ; echo " `date`: p-%p s-%s f-%f" >> /tmp/smbprn.log ; echo " `date`: j-%j J-%J z-%z c-%c" >> /tmp/smbprn.log ; rm %f </smbconfoption> + <smbconfoption name="public">no</smbconfoption> + <smbconfoption name="guest ok">no</smbconfoption> + <smbconfoption name="writable">no</smbconfoption> + <smbconfoption name="printable">yes</smbconfoption> + <smbconfoption name="printer admin">kurt</smbconfoption> + <smbconfoption name="hosts deny">0.0.0.0</smbconfoption> + <smbconfoption name="hosts allow">turbo_xp, 10.160.50.23, 10.160.51.60</smbconfoption> + </smbconfblock> + </example> + + <para> + This special share is only for testing purposes. It does not write the print job to a file. It just logs the job parameters + known to Samba into the <filename>/tmp/smbprn.log</filename> file and deletes the job-file. Moreover, the + <smbconfoption name="printer admin"/> of this share is <quote>kurt</quote> (not the <quote>@ntadmins</quote> group), + guest access is not allowed, the share isn't published to the Network Neighborhood (so you need to know it is there), and it + allows access from only three hosts. To prevent CUPS from kicking in and taking over the print jobs for that share, we need to set + <smbconfoption name="printing">sysv</smbconfoption> and <smbconfoption name="printcap">lpstat</smbconfoption>. + </para> + + </sect2> + +</sect1> + +<sect1> + <title>Advanced Configuration</title> + + <para> + Before we delve into all the configuration options, let us clarify a few points. <emphasis>Network printing + needs to be organized and set up correctly</emphasis>. This frequently doesn't happen. Legacy systems or small + business LAN environments often lack design and good housekeeping. + </para> + + + <sect2> + <title>Central Spooling vs. <quote>Peer-to-Peer</quote> Printing</title> + + + <para> +<indexterm><primary>spooling</primary></indexterm> + <indexterm><primary>spooling</primary><secondary>central</secondary></indexterm> + <indexterm><primary>spooling</primary><secondary>peer-to-peer</secondary></indexterm> + Many small office or home networks, as well as badly organized larger environments, allow each client a direct + access to available network printers. This is generally a bad idea. It often blocks one client's access to the + printer when another client's job is printing. It might freeze the first client's application while it is + waiting to get rid of the job. Also, there are frequent complaints about various jobs being printed with their + pages mixed with each other. A better concept is the use of a print server: it routes all jobs through one + central system, which responds immediately, takes jobs from multiple concurrent clients, and transfers them to + the printer(s) in the correct order. + </para> + + </sect2> + + <sect2> + <title>Raw Print Serving: Vendor Drivers on Windows Clients</title> + + <para> + <indexterm><primary>spooling-only</primary></indexterm> + <indexterm><primary>raw printing</primary></indexterm> + Most traditionally configured UNIX print servers acting on behalf of + Samba's Windows clients represented a really simple setup. Their only + task was to manage the <quote>raw</quote> spooling of all jobs handed to them by + Samba. This approach meant that the Windows clients were expected to + prepare the print job file that is ready to be sent to the printing + device. In this case, a native (vendor-supplied) Windows printer driver needs to + be installed on each and every client for the target device. + </para> + + <para> +<indexterm><primary>render</primary></indexterm> +<indexterm><primary>vendor-provided drivers</primary></indexterm> + It is possible to configure CUPS, Samba, and your Windows clients in the + same traditional and simple way. When CUPS printers are configured + for raw print-through mode operation, it is the responsibility of the + Samba client to fully render the print job (file). The file must be + sent in a format that is suitable for direct delivery to the + printer. Clients need to run the vendor-provided drivers to do + this. In this case, CUPS will not do any print file format conversion + work. + </para> + + <para> + The easiest printing configuration possible is raw print-through. + This is achieved by installation of the printer as if it were physically + attached to the Windows client. You then redirect output to a raw network + print queue. This procedure may be followed to achieve this: + </para> + + <procedure> + <title>Configuration Steps for Raw CUPS Printing Support</title> + + <step><para> +<indexterm><primary>/etc/cups/mime.types</primary></indexterm> + Edit <filename>/etc/cups/mime.types</filename> to uncomment the line + near the end of the file that has: +<screen> +#application/octet-... +</screen> + </para></step> + + <step><para> +<indexterm><primary>/etc/cups/mime.convs</primary></indexterm> + Do the same for the file <filename>/etc/cups/mime.convs</filename>. + </para></step> + + <step><para> + Add a raw printer using the Web interface. Point your browser at + <constant>http://localhost:631</constant>. Enter Administration, and add + the printer following the prompts. Do not install any drivers for it. + Choose Raw. Choose queue name <constant>Raw Queue</constant>. + </para></step> + + <step><para> + In the &smb.conf; file <constant>[printers]</constant> section add + <smbconfoption name="use client driver">Yes</smbconfoption>, + and in the <constant>[global]</constant> section add + <smbconfoption name="printing">CUPS</smbconfoption>, plus + <smbconfoption name="printcap">CUPS</smbconfoption>. + </para></step> + + <step><para> + Install the printer as if it is a local printer, that is, Printing to <constant>LPT1:</constant>. + </para></step> + + <step><para> + Edit the configuration under the <guimenu>Detail</guimenu> tab and create a + <constant>local port</constant> that points to the raw printer queue that + you have configured above. Example: <constant>\\server\raw_q</constant>. + Here, the name <constant>raw_q</constant> is the name you gave the print + queue in the CUPS environment. + </para></step> + </procedure> + + </sect2> + + <sect2> + <title>Installation of Windows Client Drivers</title> + + <para> + The printer drivers on the Windows clients may be installed + in two functionally different ways: + </para> + + <itemizedlist> + <listitem><para>Manually install the drivers locally on each client, + one by one; this yields the old LanMan style + printing and uses a <filename>\\sambaserver\printershare</filename> + type of connection.</para></listitem> + + + <listitem><para> + <indexterm><primary>point 'n' print</primary></indexterm> + Deposit and prepare the drivers (for later download) on + the print server (Samba); this enables the clients to use + <quote>Point'n'Print</quote> to get drivers semi-automatically installed the + first time they access the printer; with this method NT/200x/XP + clients use the <emphasis>SPOOLSS/MS-RPC</emphasis> + type printing calls.</para></listitem> + </itemizedlist> + + <para> + The second method is recommended for use over the first. + </para> + </sect2> + + <sect2 id="cups-raw"> + <title>Explicitly Enable <quote>raw</quote> Printing for <emphasis>application/octet-stream</emphasis></title> + + + <para> + <indexterm><primary>application/octet-stream</primary></indexterm> + <indexterm><primary>raw printing</primary></indexterm> + <indexterm><primary>MIME</primary><secondary>raw</secondary></indexterm> + If you use the first option (drivers are installed on the client + side), there is one setting to take care of: CUPS needs to be told + that it should allow <quote>raw</quote> printing of deliberate (binary) file + formats. The CUPS files that need to be correctly set for raw mode + printers to work are: + </para> + + <itemizedlist> + <listitem><para><filename>/etc/cups/mime.types</filename></para></listitem> + <listitem><para><filename>/etc/cups/mime.convs</filename></para></listitem> + </itemizedlist> + + <para> + Both contain entries (at the end of the respective files) that must be uncommented to allow RAW mode + operation. In <filename>/etc/cups/mime.types</filename>, make sure this line is present: +<programlisting> +application/octet-stream +</programlisting> + <indexterm><primary>/etc/cups/mime.convs</primary></indexterm> + <indexterm><primary>/etc/cups/mime.types</primary></indexterm> + In <filename>/etc/cups/mime.convs</filename>, have this line: + <indexterm><primary>application/vnd.cups-raw</primary></indexterm> +<programlisting> +application/octet-stream application/vnd.cups-raw 0 - +</programlisting> + If these two files are not set up correctly for raw Windows client + printing, you may encounter the dreaded <computeroutput>Unable to + convert file 0</computeroutput> in your CUPS <filename>error_log</filename> file. + </para> + + <note><para> + Editing the <filename>mime.convs</filename> and the <filename>mime.types</filename> file does + not <emphasis>enforce</emphasis> <quote>raw</quote> printing, it only <emphasis>allows</emphasis> it. + </para></note> + + <formalpara><title>Background</title> + + <para> + <indexterm><primary>application/octet-stream</primary></indexterm> +<indexterm><primary>MIME type</primary></indexterm> + That CUPS is a more security-aware printing system than traditional ones does not by default allow a user to + send deliberate (possibly binary) data to printing devices. This could be easily abused to launch a + <quote>Denial of Service</quote> attack on your printer(s), causing at least the loss of a lot of paper and + ink. <quote>Unknown</quote> data are tagged by CUPS as <parameter>MIME type: application/octet-stream</parameter> + and not allowed to go to the printer. By default, you can only send other (known) MIME types <quote>raw.</quote> + Sending data <quote>raw</quote> means that CUPS does not try to convert them and passes them to the printer + untouched. + </para> + </formalpara> + + <para> + This is all you need to know to get the CUPS/Samba combo printing + <quote>raw</quote> files prepared by Windows clients, which have vendor drivers + locally installed. If you are not interested in background information about + more advanced CUPS/Samba printing, simply skip the remaining sections + of this chapter. + </para> + + </sect2> + + <sect2> + <title>Driver Upload Methods</title> + + <para> + This section describes three familiar methods, plus one new one, by which + printer drivers may be uploaded. + </para> + + <para> + <indexterm><primary>point'n'print</primary></indexterm> + If you want to use the MS-RPC-type printing, you must upload the + drivers onto the Samba server first (<smbconfsection name="[print$]"/> + share). For a discussion on how to deposit printer drivers on the + Samba host (so the Windows clients can download and use them via + <quote>Point'n'Print</quote>), please refer to the <link linkend="classicalprinting">Classical Printing + chapter</link> of this book. There you will find a description or reference to + three methods of preparing the client drivers on the Samba server: + </para> + + <itemizedlist> + <listitem><para> + <indexterm><primary>add printer wizard</primary></indexterm> + The GUI, <quote>Add Printer Wizard</quote> <emphasis>upload-from-a-Windows-client</emphasis> method. + </para></listitem> + + <listitem><para> + The command line, <quote>smbclient/rpcclient</quote> upload-from-a-UNIX-workstation method. + </para></listitem> + + <listitem><para> + <indexterm><primary>imprints</primary></indexterm> + The Imprints tool set method. + </para></listitem> + </itemizedlist> + + <para> +<indexterm><primary>cupsaddsmb</primary></indexterm> + These three methods apply to CUPS all the same. The <command>cupsaddsmb</command> utility is a new and more + convenient way to load the Windows drivers into Samba and is provided if you use CUPS. + </para> + + <para> + <command>cupsaddsmb</command> is discussed in much detail later in this chapter. But we first + explore the CUPS filtering system and compare the Windows and UNIX printing architectures. + </para> + + </sect2> + +</sect1> + +<sect1> + <title>Advanced Intelligent Printing with PostScript Driver Download</title> + + <para> + <indexterm><primary>PostScript</primary><seealso>Ghostscript</seealso></indexterm> + We now know how to set up a <quote>dump</quote> print server, that is, a server that spools + print jobs <quote>raw</quote>, leaving the print data untouched. + </para> + + <para> + You might need to set up CUPS in a smarter way. The reasons could be manifold: + </para> + +<indexterm><primary>print statistics</primary></indexterm> +<indexterm><primary>average print run</primary></indexterm> +<indexterm><primary>print quota</primary></indexterm> + <itemizedlist> + <listitem><para>Maybe your boss wants to get monthly statistics: Which + printer did how many pages? What was the average data size of a job? + What was the average print run per day? What are the typical hourly + peaks in printing? Which department prints how much?</para></listitem> + + <listitem><para>Maybe you are asked to set up a print quota system: + Users should not be able to print more jobs once they have surpassed + a given limit per period.</para></listitem> + + <listitem><para>Maybe your previous network printing setup is a mess + and must be re-organized from a clean beginning.</para></listitem> + + <listitem><para>Maybe you are experiencing too many <quote>blue screens</quote> + originating from poorly debugged printer drivers running in NT <quote>kernel mode</quote>?</para></listitem> + </itemizedlist> + + <para> + These goals cannot be achieved by a raw print server. To build a + server meeting these requirements, you'll first need to learn + how CUPS works and how you can enable its features. + </para> + + <para> + What follows is the comparison of some fundamental concepts for + Windows and UNIX printing, then a description of the + CUPS filtering system, how it works, and how you can tweak it. + </para> + + <sect2 id="gdipost"> + <title>GDI on Windows, PostScript on UNIX</title> + + <para> + <indexterm><primary>GDI</primary></indexterm> + <indexterm><primary>PostScript</primary></indexterm> + Network printing is one of the most complicated and error-prone + day-to-day tasks any user or administrator may encounter. This is + true for all OS platforms, and there are reasons it is so. + </para> + + + <para> + <indexterm><primary>PCL</primary></indexterm> + <indexterm><primary>PDL</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>Adobe</primary></indexterm> +<indexterm><primary>page description languages</primary><see>PDL</see></indexterm> + You can't expect to throw just any file format at a printer and have it get printed. A file format conversion + must take place. The problem is that there is no common standard for print file formats across all + manufacturers and printer types. While PostScript (trademark held by Adobe) and, to an extent, PCL (trademark + held by Hewlett-Packard) have developed into semi-official <quote>standards</quote> by being the most widely + used page description languages (PDLs), there are still many manufacturers who <quote>roll their own</quote> + (their reasons may be unacceptable license fees for using printer-embedded PostScript interpreters, and so on). + </para> + + </sect2> + + <sect2> + <title>Windows Drivers, GDI, and EMF</title> + + <para> + <indexterm><primary>GDI</primary></indexterm> + <indexterm><primary>EMF</primary></indexterm> + <indexterm><primary>WYSIWYG</primary></indexterm> +<indexterm><primary>Enhanced MetaFile</primary><see>EMF</see></indexterm> + In Windows OS, the format conversion job is done by the printer drivers. On MS Windows OS platforms all + application programmers have at their disposal a built-in API, the graphical device interface (GDI), as part + and parcel of the OS itself to base themselves on. This GDI core is used as one common unified ground for all + Windows programs to draw pictures, fonts, and documents <emphasis>on screen</emphasis> as well as <emphasis>on + paper</emphasis> (print). Therefore, printer driver developers can standardize on a well-defined GDI output + for their own driver input. Achieving WYSIWYG (What You See Is What You Get) is relatively easy, because the + on-screen graphic primitives, as well as the on-paper drawn objects, come from one common source. This source, + the GDI, often produces a file format called Enhanced MetaFile (EMF). The EMF is processed by the printer + driver and converted to the printer-specific file format. + </para> + + <note><para> + <indexterm><primary>PDF</primary></indexterm> +<indexterm><primary>Xprint</primary></indexterm> +<indexterm><primary>core graphic engine</primary></indexterm> + To the GDI foundation in MS Windows, Apple has chosen to put paper and screen output on a common foundation + for its (BSD-UNIX-based, did you know?) Mac OS X and Darwin operating <indexterm><primary>X Window + System</primary></indexterm> <indexterm><primary>PostScript</primary></indexterm> + <indexterm><primary>PCL</primary></indexterm> <indexterm><primary>Xprint</primary></indexterm> systems. + Apple's <emphasis>core graphic engine</emphasis> uses a <emphasis>PDF</emphasis> derivative for all display work. + </para></note> + + <para> + The example in <link linkend="1small">Windows Printing to a Local Printer</link> illustrates local Windows + printing. + </para> + + <figure id="1small"> + <title>Windows Printing to a Local Printer.</title> + <imagefile>1small</imagefile> + </figure> + + </sect2> + + <sect2> + <title>UNIX Printfile Conversion and GUI Basics</title> + + <para> + <indexterm><primary>X Window System</primary></indexterm> + <indexterm><primary>PostScript</primary></indexterm> + <indexterm><primary>PCL</primary></indexterm> + <indexterm><primary>Xprint</primary></indexterm> + In UNIX and Linux, there is no comparable layer built into the OS kernel(s) or the X (screen display) server. + Every application is responsible for itself to create its print output. Fortunately, most use PostScript and + that at least gives some common ground. Unfortunately, there are many different levels of quality for this + PostScript. And worse, there is a huge difference (and no common root) in the way the same document is + displayed on screen and how it is presented on paper. WYSIWYG is more difficult to achieve. This goes back to + the time, decades ago, when the predecessors of X.org, designing the UNIX foundations and protocols for + graphical user interfaces, refused to take responsibility for <quote>paper output</quote>, as some had + demanded at the time, and restricted itself to <quote>on-screen only.</quote> (For some years now, the + <quote>Xprint</quote> project has been under development, attempting to build printing support into the X + framework, including a PostScript and a PCL driver, but it is not yet ready for prime time.) You can see this + unfavorable inheritance up to the present day by looking into the various <quote>font</quote> directories on + your system; there are separate ones for fonts used for X display and fonts to be used on paper. + </para> + + <formalpara> + <title>Background</title> + + <para> + <indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>color</primary></indexterm> +<indexterm><primary>linewidth</primary></indexterm> +<indexterm><primary>scale</primary></indexterm> +<indexterm><primary>distort</primary></indexterm> +<indexterm><primary>rotate</primary></indexterm> +<indexterm><primary>shift</primary></indexterm> +<indexterm><primary>raster images</primary></indexterm> +<indexterm><primary>display PostScript</primary></indexterm> +<indexterm><primary>graphical objects</primary></indexterm> + The PostScript programming language is an <quote>invention</quote> by Adobe, but its specifications have been + published extensively. Its strength lies in its powerful abilities to describe graphical objects (fonts, + shapes, patterns, lines, curves, and dots), their attributes (color, linewidth), and the way to manipulate + (scale, distort, rotate, shift) them. Because of its open specification, anybody with the skill can start + writing his or her own implementation of a PostScript interpreter and use it to display PostScript files on + screen or on paper. Most graphical output devices are based on the concept of <quote>raster images</quote> or + <quote>pixels</quote> (one notable exception is pen plotters). Of course, you can look at a PostScript file in + its textual form and you will be reading its PostScript code, the language instructions that need to be + interpreted by a rasterizer. Rasterizers produce pixel images, which may be displayed on screen by a viewer + program or on paper by a printer. + </para> + </formalpara> + </sect2> + + <sect2 id="post-and-ghost"> + <title>PostScript and Ghostscript</title> + + <para> + <indexterm><primary>PostScript</primary></indexterm> + <indexterm><primary>GhostScript</primary><seealso>PostScript</seealso></indexterm> + <indexterm><primary>PostScript</primary><secondary>RIP</secondary></indexterm> +<indexterm><primary>PostScript interpreter</primary></indexterm> +<indexterm><primary>raster image processor</primary><see>RIP</see></indexterm> + So UNIX is lacking a common ground for printing on paper and displaying on screen. Despite this unfavorable + legacy for UNIX, basic printing is fairly easy if you have PostScript printers at your disposal. The reason is + that these devices have a built-in PostScript language <quote>interpreter,</quote> also called a raster image + processor (RIP), (which makes them more expensive than other types of printers; throw PostScript toward them, + and they will spit out your printed pages. The RIP does all the hard work of converting the PostScript drawing + commands into a bitmap picture as you see it on paper, in a resolution as done by your printer. This is no + different than PostScript printing a file from a Windows origin. + </para> + + <note><para> + <indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>PPD-aware</primary></indexterm> +<indexterm><primary>PostScript Printer Description</primary><see>PPD</see></indexterm> + Traditional UNIX programs and printing systems &smbmdash; while using PostScript &smbmdash; are largely not + PPD-aware. PPDs are <quote>PostScript Printer Description</quote> files. They enable you to specify and + control all options a printer supports: duplexing, stapling, and punching. Therefore, UNIX users for a long + time couldn't choose many of the supported device and job options, unlike Windows or Apple users. But now + there is CUPS. as illustrated in <link linkend="2small">Printing to a PostScript Printer</link>. + </para> + </note> + + <figure id="2small"> + <title>Printing to a PostScript Printer.</title> + <imagefile>2small</imagefile> + </figure> + + <para> + <indexterm><primary>PDL</primary></indexterm> + However, there are other types of printers out there. These do not know how to print PostScript. They use + their own PDL, often proprietary. To print to them is much more demanding. Since your UNIX applications mostly + produce PostScript, and since these devices do not understand PostScript, you need to convert the print files + to a format suitable for your printer on the host before you can send it away. + </para> + + </sect2> + + <sect2> + <title>Ghostscript: The Software RIP for Non-PostScript Printers</title> + + <para> + <indexterm><primary>GhostScript</primary></indexterm> + Here is where Ghostscript kicks in. Ghostscript is the traditional (and quite powerful) PostScript interpreter + used on UNIX platforms. It is a RIP in software, capable of doing a <emphasis>lot</emphasis> of file format + conversions for a very broad spectrum of hardware devices as well as software file formats. Ghostscript + technology and drivers are what enable PostScript printing to non-PostScript hardware. This is shown in + <link linkend="3small">Ghostscript as a RIP for Non-PostScript Printers</link>. + </para> + + <figure id="3small"> + <title>Ghostscript as a RIP for Non-PostScript Printers.</title> + <imagefile>3small</imagefile> + </figure> + + <tip><para> +<indexterm><primary>PNG</primary></indexterm> +<indexterm><primary>AFPL</primary></indexterm> +<indexterm><primary>ESP</primary></indexterm> + Use the <quote>gs -h</quote> command to check for all built-in <quote>devices</quote> on your Ghostscript + version. If you specify a parameter of <parameter>-sDEVICE=png256</parameter> on your Ghostscript command + line, you are asking Ghostscript to convert the input into a PNG file. Naming a <quote>device</quote> on the + command line is the most important single parameter to tell Ghostscript exactly how it should render the + input. New Ghostscript versions are released at fairly regular intervals, now by artofcode LLC. They are + initially put under the <quote>AFPL</quote> license, but re-released under the GNU GPL as soon as the next + AFPL version appears. GNU Ghostscript is probably the version installed on most Samba systems. But it has some + deficiencies. <indexterm><primary>Ghostscript</primary><secondary>ESP</secondary><see>ESP + GhostScript</see></indexterm> Therefore, ESP Ghostscript was developed as an enhancement over GNU Ghostscript, + with lots of bug-fixes, additional devices, and improvements. It is jointly maintained by developers from + CUPS, Gimp-Print, MandrakeSoft, SuSE, Red Hat, and Debian. It includes the <quote>cups</quote> device + (essential to print to non-PS printers from CUPS). + </para></tip> + + </sect2> + + <sect2> + <title>PostScript Printer Description (PPD) Specification</title> + + <para> + <indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>PDL</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> + While PostScript in essence is a PDL to represent the page layout in a device-independent way, real-world + print jobs are always ending up being output on hardware with device-specific features. To take care of all + the differences in hardware and to allow for innovations, Adobe has specified a syntax and file format for + PostScript Printer Description (PPD) files. Every PostScript printer ships with one of these files. + </para> + + <para> + PPDs contain all the information about general and special features of the + given printer model: Which different resolutions can it handle? Does + it have a duplexing unit? How many paper trays are there? What media + types and sizes does it take? For each item, it also names the special + command string to be sent to the printer (mostly inside the PostScript + file) in order to enable it. + </para> + + <para> + Information from these PPDs is meant to be taken into account by the + printer drivers. Therefore, installed as part of the Windows + PostScript driver for a given printer is the printer's PPD. Where it + makes sense, the PPD features are presented in the drivers' UI dialogs + to display to the user a choice of print options. In the end, the + user selections are somehow written (in the form of special + PostScript, PJL, JCL, or vendor-dependent commands) into the PostScript + file created by the driver. + </para> + + <warning><para> + <indexterm><primary>PDF</primary></indexterm> +<indexterm><primary>PDF distilling</primary></indexterm> + A PostScript file that was created to contain device-specific commands + for achieving a certain print job output (e.g., duplexed, stapled, and + punched) on a specific target machine may not print as expected, or + may not be printable at all on other models; it also may not be fit + for further processing by software (e.g., by a PDF distilling program). + </para></warning> + </sect2> + + <sect2> + <title>Using Windows-Formatted Vendor PPDs</title> + + <para> +<indexterm><primary>CUPS</primary></indexterm> +<indexterm><primary>PPDs</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> + CUPS can handle all spec-compliant PPDs as supplied by the manufacturers for their PostScript models. Even if + a vendor does not mention our favorite OS in his or her manuals and brochures, you can safely trust this: + <emphasis>If you get the Windows NT version of the PPD, you can use it unchanged in CUPS</emphasis> and thus + access the full power of your printer just like a Windows NT user could! + </para> + + <tip><para> + To check the spec compliance of any PPD online, go to <ulink noescape="1" + url="http://www.cups.org/testppd.php">http://www.cups.org/testppd.php</ulink> and upload your PPD. You will + see the results displayed immediately. CUPS in all versions after 1.1.19 has a much stricter internal PPD + parsing and checking code enabled; in case of printing trouble, this online resource should be one of your + first pit stops. + </para></tip> + + <warning><para> + <indexterm><primary>foomatic</primary></indexterm> + <indexterm><primary>cupsomatic</primary></indexterm> + For real PostScript printers, <emphasis>do not</emphasis> use the <emphasis>Foomatic</emphasis> or + <emphasis>cupsomatic</emphasis> PPDs from Linuxprinting.org. With these devices, the original vendor-provided + PPDs are always the first choice. + </para></warning> + + <tip><para> +<indexterm><primary>W32X86/2</primary></indexterm> + If you are looking for an original vendor-provided PPD of a specific device, and you know that an NT4 box (or + any other Windows box) on your LAN has the PostScript driver installed, just use <command>smbclient + //NT4-box/print\$ -U username</command> to access the Windows directory where all printer driver files are + stored. First look in the <filename>W32X86/2</filename> subdirectory for the PPD you are seeking. + </para></tip> + </sect2> + + <sect2> + <title>CUPS Also Uses PPDs for Non-PostScript Printers</title> + + <para> +<indexterm><primary>non-PostScript</primary></indexterm> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>CUPS filtering</primary></indexterm> + CUPS also uses specially crafted PPDs to handle non-PostScript printers. These PPDs are usually not available + from the vendors (and no, you can't just take the PPD of a PostScript printer with the same model name and + hope it works for the non-PostScript version too). To understand how these PPDs work for non-PS printers, we + first need to dive deeply into the CUPS filtering and file format conversion architecture. Stay tuned. + </para> + + </sect2> + +</sect1> + +<sect1> +<title>The CUPS Filtering Architecture</title> + +<para> +<indexterm><primary>CUPS filtering</primary></indexterm> +<indexterm><primary>Ghostscript</primary></indexterm> +<indexterm><primary>MIME type</primary></indexterm> +<indexterm><primary>MIME recognition</primary></indexterm> +<indexterm><primary>MIME conversion rules</primary></indexterm> +The core of the CUPS filtering system is based on Ghostscript. In addition to Ghostscript, CUPS uses some +other filters of its own. You (or your OS vendor) may have plugged in even more filters. CUPS handles all data +file formats under the label of various MIME types. Every incoming print file is subjected to an initial +autotyping. The autotyping determines its given MIME type. A given MIME type implies zero or more possible +filtering chains relevant to the selected target printer. This section discusses how MIME types recognition +and conversion rules interact. They are used by CUPS to automatically set up a working filtering chain for any +given input data format. +</para> + +<para> +If CUPS rasterizes a PostScript file natively to a bitmap, this is done in two stages: +</para> + +<itemizedlist> + <listitem><para> +<indexterm><primary>generic raster format</primary></indexterm> +<indexterm><primary>CUPS raster</primary></indexterm> + The first stage uses a Ghostscript device named <quote>cups</quote> + (this is since version 1.1.15) and produces a generic raster format + called <quote>CUPS raster</quote>. + </para></listitem> + + <listitem><para> +<indexterm><primary>raster driver</primary></indexterm> + The second stage uses a <quote>raster driver</quote> that converts + the generic CUPS raster to a device-specific raster. + </para></listitem> +</itemizedlist> + +<para> +<indexterm><primary>Ghostscript</primary></indexterm> +<indexterm><primary>GNU Ghostscript</primary></indexterm> +<indexterm><primary>ESP Ghostscript</primary></indexterm> +Make sure your Ghostscript version has the <quote>cups</quote> device compiled in (check with <command>gs -h | +grep cups</command>). Otherwise you may encounter the dreaded <computeroutput>Unable to convert file +0</computeroutput> in your CUPS error_log file. To have <quote>cups</quote> as a device in your Ghostscript, +you either need to patch GNU Ghostscript and recompile or use +<indexterm><primary>ESP</primary><secondary>Ghostscript</secondary></indexterm><ulink +url="http://www.cups.org/ghostscript.php">ESP Ghostscript</ulink>. The superior alternative is ESP +Ghostscript. It supports not just CUPS, but 300 other devices (while GNU Ghostscript supports only about 180). +Because of this broad output device support, ESP Ghostscript is the first choice for non-CUPS spoolers, too. +It is now recommended by Linuxprinting.org for all spoolers. +</para> + +<para> +<indexterm><primary>cupsomatic</primary></indexterm> +<indexterm><primary>foomatic</primary></indexterm> +<indexterm><primary>foomatic-rip</primary></indexterm> +<indexterm><primary>ESP Ghostscript</primary></indexterm> +CUPS printers may be set up to use external rendering paths. One of the most common is provided by the +Foomatic/cupsomatic concept from <ulink url="http://www.linuxprinting.org/">Linuxprinting.org</ulink>. This +uses the classical Ghostscript approach, doing everything in one step. It does not use the +<quote>cups</quote> device, but one of the many others. However, even for Foomatic/cupsomatic usage, best +results and <indexterm><primary>ESP</primary><secondary>Ghostscript</secondary></indexterm> broadest printer +model support is provided by ESP Ghostscript (more about Foomatic/cupsomatic, particularly the new version +called now <emphasis>foomatic-rip</emphasis>, follows). +</para> + + <sect2> + <title>MIME Types and CUPS Filters</title> + + + <para> + <indexterm><primary>MIME</primary><secondary>filters</secondary></indexterm> + <indexterm><primary>MIME</primary></indexterm> +<indexterm><primary>mime.types</primary></indexterm> +<indexterm><primary>application/pdf</primary></indexterm> +<indexterm><primary>autotyping</primary></indexterm> + CUPS reads the file <filename>/etc/cups/mime.types</filename> (and all other files carrying a + <filename>*.types</filename> suffix in the same directory) upon startup. These files contain the MIME type + recognition rules that are applied when CUPS runs its autotyping routines. The rule syntax is explained in the + man page for <filename>mime.types</filename> and in the comments section of the + <filename>mime.types</filename> file itself. A simple rule reads like this: + <indexterm><primary>application/pdf</primary></indexterm> +<programlisting> +application/pdf pdf string(0,%PDF) +</programlisting> +<indexterm><primary>%PDF</primary></indexterm> +<indexterm><primary>.pdf</primary></indexterm> + This means if a filename has a <filename>.pdf</filename> suffix or if the magic string + <emphasis>%PDF</emphasis> is right at the beginning of the file itself (offset 0 from the start), then it is a + PDF file (<parameter>application/pdf</parameter>). Another rule is this: +<programlisting> +application/postscript ai eps ps string(0,%!) string(0,<04>%!) +</programlisting> +<indexterm><primary>suffixes</primary></indexterm> +<indexterm><primary>.ai</primary></indexterm> +<indexterm><primary>.eps</primary></indexterm> +<indexterm><primary>.ps</primary></indexterm> +<indexterm><primary>generic PostScript</primary></indexterm> +<indexterm><primary>application/postscript</primary></indexterm> + If the filename has one of the suffixes <filename>.ai</filename>, <filename>.eps</filename>, + <filename>.ps</filename>, or if the file itself starts with one of the strings <emphasis>%!</emphasis> or + <emphasis><![CDATA[<04>%!]]></emphasis>, it is a generic PostScript file + (<parameter>application/postscript</parameter>). + </para> + + <warning><para> +<indexterm><primary>/etc/cups/</primary></indexterm> + Don't confuse the other mime.types files your system might be using + with the one in the <filename>/etc/cups/</filename> directory. + </para></warning> + + <note><para> +<indexterm><primary>application/postscript</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>filter</primary></indexterm> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>transformation</primary></indexterm> + There is an important difference between two similar MIME types in CUPS: one is + <parameter>application/postscript</parameter>, the other is + <parameter>application/vnd.cups-postscript</parameter>. While <parameter>application/postscript</parameter> is + meant to be device-independent, job options for the file are still outside the PS file content, embedded in + command-line or environment variables by CUPS, <parameter>application/vnd.cups-postscript</parameter> may have + the job options inserted into the PostScript data itself (where applicable). The transformation of the generic + PostScript (<parameter>application/postscript</parameter>) to the device-specific version + (<parameter>application/vnd.cups-postscript</parameter>) is the responsibility of the CUPS + <parameter>pstops</parameter> filter. pstops uses information contained in the PPD to do the transformation. + </para></note> + + <para> +<indexterm><primary>ASCII</primary></indexterm> +<indexterm><primary>HP-GL</primary></indexterm> +<indexterm><primary>PDF</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>DVI</primary></indexterm> +<indexterm><primary>GIF</primary></indexterm> +<indexterm><primary>PNG</primary></indexterm> +<indexterm><primary>TIFF</primary></indexterm> +<indexterm><primary>JPEG</primary></indexterm> +<indexterm><primary>Photo-CD</primary></indexterm> +<indexterm><primary>SUN-Raster</primary></indexterm> +<indexterm><primary>PNM</primary></indexterm> +<indexterm><primary>PBM</primary></indexterm> +<indexterm><primary>SGI-RGB</primary></indexterm> +<indexterm><primary>MIME</primary></indexterm> +<indexterm><primary>filters</primary></indexterm> + CUPS can handle ASCII text, HP-GL, PDF, PostScript, DVI, and + many image formats (GIF, PNG, TIFF, JPEG, Photo-CD, SUN-Raster, + PNM, PBM, SGI-RGB, and more) and their associated MIME types + with its filters. + </para> + + </sect2> + + <sect2> + <title>MIME Type Conversion Rules</title> + + + <para> + <indexterm><primary>MIME</primary></indexterm> + <indexterm><primary>application/pdf</primary></indexterm> +<indexterm><primary>/etc/cups/mime.convs</primary></indexterm> +<indexterm><primary>application/pdf</primary></indexterm> +<indexterm><primary>application/postscript</primary></indexterm> + CUPS reads the file <filename>/etc/cups/mime.convs</filename> + (and all other files named with a <filename>*.convs</filename> + suffix in the same directory) upon startup. These files contain + lines naming an input MIME type, an output MIME type, a format + conversion filter that can produce the output from the input type, + and virtual costs associated with this conversion. One example line + reads like this: +<programlisting> +application/pdf application/postscript 33 pdftops +</programlisting> +<indexterm><primary>pdftops</primary></indexterm> + This means that the <parameter>pdftops</parameter> filter will take + <parameter>application/pdf</parameter> as input and produce + <parameter>application/postscript</parameter> as output; the virtual + cost of this operation is 33 CUPS-$. The next filter is more + expensive, costing 66 CUPS-$: + <indexterm><primary>pdf</primary></indexterm> +<programlisting> +application/vnd.hp-HPGL application/postscript 66 hpgltops +</programlisting> +<indexterm><primary>hpgltops</primary></indexterm> + This is the <parameter>hpgltops</parameter>, which processes HP-GL + plotter files to PostScript. + <indexterm><primary>application/octet-stream</primary></indexterm> +<programlisting> +application/octet-stream +</programlisting> + Here are two more examples: + <indexterm><primary>text/plain</primary></indexterm> +<indexterm><primary>application/x-shell</primary></indexterm> +<indexterm><primary>text/plain</primary></indexterm> +<indexterm><primary>texttops</primary></indexterm> +<programlisting> +application/x-shell application/postscript 33 texttops +text/plain application/postscript 33 texttops +</programlisting> +<indexterm><primary>application/x-shell</primary></indexterm> + The last two examples name the <parameter>texttops</parameter> filter to work on + <parameter>text/plain</parameter> as well as on <parameter>application/x-shell</parameter>. (Hint: This + differentiation is needed for the syntax highlighting feature of <parameter>texttops</parameter>). + </para> + </sect2> + + <sect2> + <title>Filtering Overview</title> + + <para> + <indexterm><primary>MIME</primary></indexterm> + There are many more combinations named in <filename>mime.convs</filename>. However, you are not limited to use + the ones predefined there. You can plug in any filter you like to the CUPS framework. It must meet, or must be + made to meet, some minimal requirements. If you find (or write) a cool conversion filter of some kind, make + sure it complies with what CUPS needs and put in the right lines in <filename>mime.types</filename> and + <filename>mime.convs</filename>; then it will work seamlessly inside CUPS. + </para> + + <sect3> + <title>Filter Requirements</title> + + <para> + The <quote>CUPS requirements</quote> for filters are simple. Take filenames or <filename>stdin</filename> as + input and write to <filename>stdout</filename>. They should take these arguments: + </para> + + <variablelist> + <varlistentry><term>printer</term> + <listitem><para> + The name of the printer queue (normally this is the name of the filter being run). + </para></listitem> + </varlistentry> + + <varlistentry><term>job</term> + <listitem><para> + The numeric job ID for the job being printed. + </para></listitem> + </varlistentry> + + <varlistentry><term>user</term> + <listitem><para> + The string from the originating-user-name attribute. + </para></listitem> + </varlistentry> + + <varlistentry><term>title</term> + <listitem><para> + The string from the job-name attribute. + </para></listitem> + </varlistentry> + + <varlistentry><term>copies</term> + <listitem><para> + The numeric value from the number-copies attribute. + </para></listitem> + </varlistentry> + + <varlistentry><term>options</term> + <listitem><para> + The job options. + </para></listitem> + </varlistentry> + + <varlistentry><term>filename</term> + <listitem><para> + (optionally) The print request file (if missing, filters expected data + fed through <filename>stdin</filename>). In most cases, it is easy to + write a simple wrapper script around existing filters to make them work with CUPS. + </para></listitem> + </varlistentry> + </variablelist> + + </sect3> + + </sect2> + + <sect2> + <title>Prefilters</title> + + <para> + <indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>non-PostScript printers</primary></indexterm> +<indexterm><primary>raster</primary></indexterm> + As previously stated, PostScript is the central file format to any UNIX-based + printing system. From PostScript, CUPS generates raster data to feed + non-PostScript printers. + </para> + + <para> +<indexterm><primary>prefilters</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>ASCII text</primary></indexterm> +<indexterm><primary>PDF</primary></indexterm> +<indexterm><primary>DVI</primary></indexterm> +<indexterm><primary>HP-GL.</primary></indexterm> +<indexterm><primary>MIME type</primary></indexterm> +<indexterm><primary>application/postscript</primary></indexterm> +<indexterm><primary>pstops</primary></indexterm> +<indexterm><primary>application/vnd.cups-postscript</primary></indexterm> + But what happens if you send one of the supported non-PS formats to print? Then CUPS runs + <quote>prefilters</quote> on these input formats to generate PostScript first. There are prefilters to create + PostScript from ASCII text, PDF, DVI, or HP-GL. The outcome of these filters is always of MIME type + <parameter>application/postscript</parameter> (meaning that any device-specific print options are not yet + embedded into the PostScript by CUPS and that the next filter to be called is pstops). Another prefilter is + running on all supported image formats, the <parameter>imagetops</parameter> filter. Its outcome is always of + MIME type <parameter>application/vnd.cups-postscript</parameter> (not application/postscript), meaning it has + the print options already embedded into the file. This is shown in <link linkend="4small">Prefiltering in + CUPS to Form PostScript</link>. + </para> + + <figure id="4small"> + <title>Prefiltering in CUPS to Form PostScript.</title> + <imagefile scale="25">4small</imagefile> + </figure> + + </sect2> + + <sect2> + <title>pstops</title> + + <para> +<indexterm><primary>pstops</primary></indexterm> +<indexterm><primary>application/postscript</primary></indexterm> +<indexterm><primary>application/vnd.cups-postscript</primary></indexterm> +<indexterm><primary>output duplexing</primary></indexterm> +<indexterm><primary>stapling</primary></indexterm> +<indexterm><primary>punching</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> + <emphasis>pstops</emphasis> is a filter that is used to convert <parameter>application/postscript</parameter> to + <parameter>application/vnd.cups-postscript</parameter>. As stated earlier, this filter inserts all + device-specific print options (commands to the printer to ask for the duplexing of output, or stapling and + punching it, and so on) into the PostScript file. An example is illustrated in <link + linkend="5small">Adding Device-Specific Print Options</link>. + </para> + + <figure id="5small"> + <title>Adding Device-Specific Print Options.</title> + <imagefile scale="25">5small</imagefile> + </figure> + + <para> + This is not all. Other tasks performed by it are: + </para> + + <itemizedlist> + <listitem><para> + Selecting the range of pages to be printed (e.g., you can choose to + print only pages <quote>3, 6, 8-11, 16, and 19-21</quote>, or only odd-numbered + pages). + </para></listitem> + + <listitem><para> + Putting two or more logical pages on one sheet of paper (the + so-called <quote>number-up</quote> function). + </para></listitem> + + <listitem><para>Counting the pages of the job to insert the accounting + information into the <filename>/var/log/cups/page_log</filename>. + </para></listitem> + </itemizedlist> + </sect2> + + <sect2> + <title>pstoraster</title> + + <para> +<indexterm><primary>pstoraster</primary></indexterm> +<indexterm><primary>rasterization</primary></indexterm> +<indexterm><primary>raster drivers</primary></indexterm> + <parameter>pstoraster</parameter> is at the core of the CUPS filtering system. It is responsible for the first + stage of the rasterization process. Its input is of MIME type application/vnd.cups-postscript; its output is + application/vnd.cups-raster. This output format is not yet meant to be printable. Its aim is to serve as a + general-purpose input format for more specialized <emphasis>raster drivers</emphasis> that are able to + generate device-specific printer data. This is shown in <link linkend="cups-raster">the PostScript to + Intermediate Raster Format diagram</link>. + </para> + + <figure id="cups-raster"> + <title>PostScript to Intermediate Raster Format.</title> + <imagefile scale="25">6small</imagefile> + </figure> + + <para> +<indexterm><primary>CUPS raster</primary></indexterm> +<indexterm><primary>generic raster</primary></indexterm> +<indexterm><primary>IANA</primary></indexterm> +<indexterm><primary>raster drivers</primary></indexterm> + CUPS raster is a generic raster format with powerful features. It is able to include per-page information, + color profiles, and more, to be used by the downstream raster drivers. Its MIME type is registered with IANA + and its specification is, of course, completely open. It is designed to make it quite easy and inexpensive for + manufacturers to develop Linux and UNIX raster drivers for their printer models should they choose to do so. + CUPS always takes care of the first stage of rasterization so these vendors do not need to care about + Ghostscript complications (in fact, there are currently more than one vendor financing the development of CUPS + raster drivers). This is illustrated in <link linkend="cups-raster2">the CUPS-Raster Production Using + Ghostscript illustration</link>. + </para> + + <figure id="cups-raster2"> + <title>CUPS-Raster Production Using Ghostscript.</title> + <imagefile>7small</imagefile> + </figure> + + <para> +<indexterm><primary>pstoraster</primary></indexterm> +<indexterm><primary>GNU Ghostscript</primary></indexterm> +<indexterm><primary>AFPL Ghostscript</primary></indexterm> +<indexterm><primary>standalone filter</primary></indexterm> + CUPS versions before version 1.1.15 shipped a binary (or source code) standalone filter, named + <parameter>pstoraster</parameter>. <parameter>pstoraster</parameter>, which was derived from GNU Ghostscript + 5.50 and could be installed instead of and in addition to any GNU or AFPL Ghostscript package without + conflicting. + </para> + + <para> + Since version 1.1.15, this feature has changed. The functions for this filter have been integrated back + into Ghostscript (now based on GNU Ghostscript version 7.05). The <parameter>pstoraster</parameter> filter is + now a simple shell script calling <command>gs</command> with the <command>-sDEVICE=cups</command> parameter. + If your Ghostscript fails when this command is executed: <command>gs -h |grep cups</command>, you might not + be able to print, update your Ghostscript. + </para> + </sect2> + + <sect2> + <title>imagetops and imagetoraster</title> + + <para> +<indexterm><primary>prefilter</primary></indexterm> +<indexterm><primary>imagetoraster</primary></indexterm> + In the section about prefilters, we mentioned the prefilter + that generates PostScript from image formats. The <parameter>imagetoraster</parameter> + filter is used to convert directly from image to raster, without the + intermediate PostScript stage. It is used more often than the previously + mentioned prefilters. We summarize in a flowchart the image file + filtering in <link linkend="small8">the Image Format to CUPS-Raster Format Conversion illustration</link>. + </para> + + <figure id="small8"> + <title>Image Format to CUPS-Raster Format Conversion.</title> + <imagefile>8small</imagefile> + </figure> + + </sect2> + + <sect2> + <title>rasterto [printers specific]</title> + + <para> +<indexterm><primary>rastertoalps</primary></indexterm> +<indexterm><primary>rastertobj</primary></indexterm> +<indexterm><primary>rastertoepson</primary></indexterm> +<indexterm><primary>rastertoescp</primary></indexterm> +<indexterm><primary>rastertopcl</primary></indexterm> +<indexterm><primary>rastertoturboprint</primary></indexterm> +<indexterm><primary>rastertoescp</primary></indexterm> +<indexterm><primary>rastertohp</primary></indexterm> +<indexterm><primary>rastertoprinter</primary></indexterm> +<indexterm><primary>rastertoprinter</primary></indexterm> +<indexterm><primary>Gimp-Print</primary></indexterm> + CUPS ships with quite a variety of raster drivers for processing CUPS raster. On my system, I find in + /usr/lib/cups/filter/ the following: <parameter>rastertoalps</parameter>, <parameter>rastertobj</parameter>, + <parameter>rastertoepson</parameter>, <parameter>rastertoescp</parameter>, <parameter>rastertopcl</parameter>, + <parameter>rastertoturboprint</parameter>, <parameter>rastertoapdk</parameter>, + <parameter>rastertodymo</parameter>, <parameter>rastertoescp</parameter>, <parameter>rastertohp</parameter>, + and <parameter>rastertoprinter</parameter>. Don't worry if you have fewer drivers than this; some of these are + installed by commercial add-ons to CUPS (like <parameter>rastertoturboprint</parameter>), and others (like + <parameter>rastertoprinter</parameter>) by third-party driver development projects (such as Gimp-Print) + wanting to cooperate as closely as possible with CUPS. See <link linkend="small9">the Raster to + Printer-Specific Formats illustration</link>. + </para> + + <figure id="small9"> + <title>Raster to Printer-Specific Formats.</title> + <imagefile>9small</imagefile> + </figure> + </sect2> + + <sect2> + <title>CUPS Backends</title> + + <para> +<indexterm><primary>CUPS filtering chain</primary></indexterm> +<indexterm><primary>print queue</primary></indexterm> + The last part of any CUPS filtering chain is a backend. Backends + are special programs that send the print-ready file to the final + device. There is a separate backend program for any transfer + protocol for sending print jobs over the network, and one for every local + interface. Every CUPS print queue needs to have a CUPS <quote>device-URI</quote> + associated with it. The device URI is the way to encode the backend + used to send the job to its destination. Network device-URIs use + two slashes in their syntax, local device URIs only one, as you can + see from the following list. Keep in mind that local interface names + may vary greatly from my examples, if your OS is not Linux: + </para> + + <variablelist> + <varlistentry><term>usb</term> + <listitem><para> + This backend sends print files to USB-connected printers. An + example for the CUPS device-URI to use is + <filename>usb:/dev/usb/lp0</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>serial</term> + <listitem><para> + This backend sends print files to serially connected printers. + An example for the CUPS device-URI to use is + <filename>serial:/dev/ttyS0?baud=11500</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>parallel</term> + <listitem><para> + This backend sends print files to printers connected to the + parallel port. An example for the CUPS device-URI to use is + <filename>parallel:/dev/lp0</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>SCSI</term> + <listitem><para> + This backend sends print files to printers attached to the + SCSI interface. An example for the CUPS device-URI to use is + <filename>scsi:/dev/sr1</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>lpd</term> + <listitem><para> + This backend sends print files to LPR/LPD-connected network + printers. An example for the CUPS device-URI to use is + <filename>lpd://remote_host_name/remote_queue_name</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>AppSocket/HP JetDirect</term> + <listitem><para> + This backend sends print files to AppSocket (a.k.a., HP + JetDirect) connected network printers. An example for the CUPS + device-URI to use is + <filename>socket://10.11.12.13:9100</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>ipp</term> + <listitem><para> + This backend sends print files to IPP-connected network + printers (or to other CUPS servers). Examples for CUPS device-URIs + to use are + <filename>ipp:://192.193.194.195/ipp</filename> + (for many HP printers) and + <filename>ipp://remote_cups_server/printers/remote_printer_name</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>http</term> + <listitem><para> + This backend sends print files to HTTP-connected printers. + (The http:// CUPS backend is only a symlink to the ipp:// backend.) + Examples for the CUPS device-URIs to use are + <filename>http:://192.193.194.195:631/ipp</filename> + (for many HP printers) and + <filename>http://remote_cups_server:631/printers/remote_printer_name</filename>. + </para></listitem></varlistentry> + + <varlistentry><term>smb</term> + <listitem><para> + This backend sends print files to printers shared by a Windows + host. Examples of CUPS device-URIs that may be used includes: + </para> + + <para> + <simplelist> + <member><filename>smb://workgroup/server/printersharename</filename></member> + <member><filename>smb://server/printersharename</filename></member> + <member><filename>smb://username:password@workgroup/server/printersharename</filename></member> + <member><filename>smb://username:password@server/printersharename</filename></member> + </simplelist> + </para> + + <para> + The smb:// backend is a symlink to the Samba utility + <parameter>smbspool</parameter> (does not ship with CUPS). If the + symlink is not present in your CUPS backend directory, have your + root user create it: <command>ln -s `which smbspool' + /usr/lib/cups/backend/smb</command>. + </para></listitem></varlistentry> + </variablelist> + + <para> + It is easy to write your own backends as shell or Perl scripts if you + need any modification or extension to the CUPS print system. One + reason could be that you want to create <quote>special</quote> printers that send + the print jobs as email (through a <quote>mailto:/</quote> backend), convert them to + PDF (through a <quote>pdfgen:/</quote> backend) or dump them to <quote>/dev/null</quote>. (In + fact, I have the systemwide default printer set up to be connected to + a devnull:/ backend: there are just too many people sending jobs + without specifying a printer, and scripts and programs that do not name + a printer. The systemwide default deletes the job and sends a polite + email back to the $USER asking him or her to always specify the correct + printer name.) + </para> + + <para> +<indexterm><primary>lpinfo</primary></indexterm> +<indexterm><primary>CUPS backends</primary></indexterm> + Not all of the mentioned backends may be present on your system or + usable (depending on your hardware configuration). One test for all + available CUPS backends is provided by the <emphasis>lpinfo</emphasis> + utility. Used with the <option>-v</option> parameter, it lists + all available backends: + </para> + + <para><screen> + &prompt;<userinput>lpinfo -v</userinput> + </screen></para> + </sect2> + + <sect2> + <title>The Role of <parameter>cupsomatic/foomatic</parameter></title> + + <para> + <indexterm><primary>cupsomatic</primary></indexterm> + <indexterm><primary>foomatic</primary></indexterm> +<indexterm><primary>PPDs</primary></indexterm> +<indexterm><primary>Foomatic Printer</primary></indexterm> +<indexterm><primary>Linuxprinting.org</primary></indexterm> + <parameter>cupsomatic</parameter> filters may be the most widely used on CUPS + installations. You must be clear that these were not + developed by the CUPS people. They are a third-party add-on to + CUPS. They utilize the traditional Ghostscript devices to render jobs + for CUPS. When troubleshooting, you should know about the + difference. Here the whole rendering process is done in one stage, + inside Ghostscript, using an appropriate device for the target + printer. <parameter>cupsomatic</parameter> uses PPDs that are generated from the Foomatic + Printer & Driver Database at Linuxprinting.org. + </para> + + <para> + You can recognize these PPDs from the line calling the + <parameter>cupsomatic</parameter> filter: +<programlisting> +*cupsFilter: "application/vnd.cups-postscript 0 cupsomatic" +</programlisting> + You may find this line among the first 40 or so lines of the PPD + file. If you have such a PPD installed, the printer shows up in the + CUPS Web interface with a <parameter>foomatic</parameter> namepart for + the driver description. <parameter>cupsomatic</parameter> is a Perl script that runs + Ghostscript with all the complicated command-line options + autoconstructed from the selected PPD and command line options give to + the print job. + </para> + + <para> + <indexterm><primary>point'n'print</primary></indexterm> +<indexterm><primary>foomatic-rip</primary></indexterm> +<indexterm><primary>Adobe specifications</primary></indexterm> +<indexterm><primary>hi-res photo</primary></indexterm> +<indexterm><primary>normal color</primary></indexterm> +<indexterm><primary>grayscale</primary></indexterm> +<indexterm><primary>draft</primary></indexterm> +<indexterm><primary>media type</primary></indexterm> +<indexterm><primary>resolution</primary></indexterm> +<indexterm><primary>inktype</primary></indexterm> +<indexterm><primary>dithering algorithm</primary></indexterm> + However, <parameter>cupsomatic</parameter> is now deprecated. Its PPDs (especially the first + generation of them, still in heavy use out there) are not meeting the + Adobe specifications. You might also suffer difficulties when you try + to download them with <quote>Point'n'Print</quote> to Windows clients. A better + and more powerful successor is now in a stable beta-version: it is called <parameter>foomatic-rip</parameter>. To use + <parameter>foomatic-rip</parameter> as a filter with CUPS, you need the new type of PPDs, which + have a similar but different line: +<programlisting> +*cupsFilter: "application/vnd.cups-postscript 0 foomatic-rip" +</programlisting> + The PPD-generating engine at Linuxprinting.org has been revamped. + The new PPDs comply with the Adobe spec. They also provide a + new way to specify different quality levels (hi-res photo, normal + color, grayscale, and draft) with a single click, whereas before you + could have required five or more different selections (media type, + resolution, inktype, and dithering algorithm). There is support for + custom-size media built in. There is support to switch + print options from page to page in the middle of a job. And the + best thing is that the new <constant>foomatic-rip</constant> works seamlessly with all + legacy spoolers too (like LPRng, BSD-LPD, PDQ, PPR, and so on), providing + for them access to use PPDs for their printing. + </para> + </sect2> + + <sect2> + <title>The Complete Picture</title> + + <para> + If you want to see an overview of all the filters and how they + relate to each other, the complete picture of the puzzle is at the end + of this chapter. + </para> + </sect2> + + <sect2> + <title><filename>mime.convs</filename></title> + + <para> + CUPS autoconstructs all possible filtering chain paths for any given + MIME type and every printer installed. But how does it decide in + favor of or against a specific alternative? (There may be cases + where there is a choice of two or more possible filtering chains for + the same target printer.) Simple. You may have noticed the figures in + the third column of the mime.convs file. They represent virtual costs + assigned to this filter. Every possible filtering chain will sum up to + a total <quote>filter cost.</quote> CUPS decides for the most <quote>inexpensive</quote> route. + </para> + + <tip><para> +<indexterm><primary>cupsd.conf</primary></indexterm> +<indexterm><primary>FilterLimit</primary></indexterm> + Setting <parameter>FilterLimit 1000</parameter> in + <filename>cupsd.conf</filename> will not allow more filters to + run concurrently than will consume a total of 1000 virtual filter + cost. This is an efficient way to limit the load of any CUPS + server by setting an appropriate <quote>FilterLimit</quote> value. A FilterLimit of + 200 allows roughly one job at a time, while a FilterLimit of 1000 allows + approximately five jobs maximum at a time. + </para></tip> + </sect2> + + <sect2> + <title><quote>Raw</quote> Printing</title> + + <para> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>lpadmin</primary></indexterm> +<indexterm><primary>rawprinter</primary></indexterm> + You can tell CUPS to print (nearly) any file <quote>raw</quote>. <quote>Raw</quote> means it will not be + filtered. CUPS will send the file to the printer <quote>as is</quote> without bothering if the printer is able + to digest it. Users need to take care themselves that they send sensible data formats only. Raw printing can + happen on any queue if the <quote><parameter>-o raw</parameter></quote> option is specified on the command + line. You can also set up raw-only queues by simply not associating any PPD with it. This command: +<screen> +&prompt;<userinput>lpadmin -P rawprinter -v socket://11.12.13.14:9100 -E</userinput> +</screen> + sets up a queue named <quote>rawprinter</quote>, connected via the <quote>socket</quote> protocol (a.k.a. + <quote>HP JetDirect</quote>) to the device at IP address 11.12.1.3.14, using port 9100. (If you had added a + PPD with <command>-P /path/to/PPD</command> to this command line, you would have installed a + <quote>normal</quote> print queue.) + </para> + + <para> + CUPS will automatically treat each job sent to a queue as a <quote>raw</quote> one + if it can't find a PPD associated with the queue. However, CUPS will + only send known MIME types (as defined in its own mime.types file) and + refuse others. + </para> + </sect2> + + <sect2> + <title>application/octet-stream Printing</title> + + <para> +<indexterm><primary>/etc/cups/mime.types</primary></indexterm> +<indexterm><primary>application/octet-stream</primary></indexterm> + Any MIME type with no rule in the <filename>/etc/cups/mime.types</filename> file is regarded as unknown + or <parameter>application/octet-stream</parameter> and will not be + sent. Because CUPS refuses to print unknown MIME types by default, + you will probably have experienced that print jobs originating + from Windows clients were not printed. You may have found an error + message in your CUPS logs like: + </para> + + <para><computeroutput> + Unable to convert file 0 to printable format for job + </computeroutput></para> + + <para> + To enable the printing of <parameter>application/octet-stream</parameter> files, edit + these two files: + </para> + + <itemizedlist> + <listitem><para><filename>/etc/cups/mime.convs</filename></para></listitem> + + <listitem><para><filename>/etc/cups/mime.types</filename></para></listitem> + </itemizedlist> + + <para> +<indexterm><primary>raw mode</primary></indexterm> + Both contain entries (at the end of the respective files) that must be uncommented to allow raw mode + operation for <parameter>application/octet-stream</parameter>. In <filename>/etc/cups/mime.types</filename> + make sure this line is present: + <indexterm><primary>application/octet-stream</primary></indexterm> +<programlisting> +application/octet-stream +</programlisting> + This line (with no specific autotyping rule set) makes all files + not otherwise auto-typed a member of <parameter>application/octet-stream</parameter>. In + <filename>/etc/cups/mime.convs</filename>, have this + line: +<programlisting> +application/octet-stream application/vnd.cups-raw 0 - +</programlisting> + <indexterm><primary>MIME</primary></indexterm> + This line tells CUPS to use the <emphasis>Null Filter</emphasis> + (denoted as <quote>-</quote>, doing nothing at all) on + <parameter>application/octet-stream</parameter>, and tag the result as + <parameter>application/vnd.cups-raw</parameter>. This last one is + always a green light to the CUPS scheduler to now hand the file over + to the backend connecting to the printer and sending it over. + </para> + + <note><para> + Editing the <filename>mime.convs</filename> and the <filename>mime.types</filename> file does not + <emphasis>enforce</emphasis> <quote>raw</quote> printing, it only <emphasis>allows</emphasis> it. + </para></note> + + <formalpara> + <title>Background</title> + + <para> +<indexterm><primary>security-aware</primary></indexterm> +<indexterm><primary>MIME type</primary></indexterm> +<indexterm><primary>/etc/cups/mime.types</primary></indexterm> +<indexterm><primary>/etc/cups/mime.convs</primary></indexterm> + That CUPS is a more security-aware printing system than traditional ones + does not by default allow one to send deliberate (possibly binary) + data to printing devices. (This could be easily abused to launch a + Denial of Service attack on your printer(s), causing at least the loss + of a lot of paper and ink.) <quote>Unknown</quote> data are regarded by CUPS + as <emphasis>MIME type</emphasis> <emphasis>application/octet-stream</emphasis>. While you + <emphasis>can</emphasis> send data <quote>raw</quote>, the MIME type for these must + be one that is known to CUPS and allowed by it. The file + <filename>/etc/cups/mime.types</filename> defines the <quote>rules</quote> of how CUPS + recognizes MIME types. The file <filename>/etc/cups/mime.convs</filename> decides which file + conversion filter(s) may be applied to which MIME types. + </para> + </formalpara> + </sect2> + + <sect2> + <title>PostScript Printer Descriptions for Non-PostScript Printers</title> + + <para> + <indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>non-PostScript</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>RIP</primary></indexterm> +<indexterm><primary>Ghostscript</primary></indexterm> +<indexterm><primary>device-specific commands</primary></indexterm> + Originally PPDs were meant to be used for PostScript printers + only. Here, they help to send device-specific commands and settings + to the RIP, which processes the job file. CUPS has extended this + scope for PPDs to cover non-PostScript printers too. This was not + difficult, because it is a standardized file format. In a way + it was logical too: CUPS handles PostScript and uses a PostScript + RIP (Ghostscript) to process the job files. The only difference is that + a PostScript printer has the RIP built-in, for other types of + printers the Ghostscript RIP runs on the host computer. + </para> + + <para> + PPDs for a non-PostScript printer have a few lines that are unique to + CUPS. The most important one looks similar to this: + <indexterm><primary>application/vnd.cups-raster</primary></indexterm> +<programlisting> +*cupsFilter: application/vnd.cups-raster 66 rastertoprinter +</programlisting> + It is the last piece in the CUPS filtering puzzle. This line tells the + CUPS daemon to use as a last filter <parameter>rastertoprinter</parameter>. This filter + should be served as input an <parameter>application/vnd.cups-raster</parameter> MIME type + file. Therefore, CUPS should autoconstruct a filtering chain, which + delivers as its last output the specified MIME type. This is then + taken as input to the specified <parameter>rastertoprinter</parameter> filter. After + the last filter has done its work (<parameter>rastertoprinter</parameter> is a Gimp-Print + filter), the file should go to the backend, which sends it to the + output device. + </para> + + <para> + CUPS by default ships only a few generic PPDs, but they are good for + several hundred printer models. You may not be able to control + different paper trays, or you may get larger margins than your + specific model supports. See Table 21.1<link linkend="cups-ppds"></link> for summary information. + </para> + + <table frame="all" id="cups-ppds"> + <title>PPDs Shipped with CUPS</title> + <tgroup cols="2" align="left"> + <colspec align="left"/> + <colspec align="justify" colwidth="1*"/> + <thead><row><entry>PPD file</entry><entry>Printer type</entry></row></thead> + <tbody> + <row><entry>deskjet.ppd</entry><entry>older HP inkjet printers and compatible</entry></row> + + <row><entry>deskjet2.ppd</entry> <entry>newer HP inkjet printers and compatible </entry> </row> + + <row><entry>dymo.ppd</entry> <entry>label printers </entry> </row> + + <row><entry>epson9.ppd</entry> <entry>Epson 24-pin impact printers and compatible </entry> </row> + + <row><entry>epson24.ppd</entry> <entry>Epson 24-pin impact printers and compatible </entry> </row> + + <row><entry>okidata9.ppd</entry> <entry>Okidata 9-pin impact printers and compatible </entry> </row> + + <row><entry>okidat24.ppd</entry> <entry>Okidata 24-pin impact printers and compatible </entry> </row> + + <row><entry>stcolor.ppd</entry> <entry>older Epson Stylus Color printers </entry> </row> + + <row><entry>stcolor2.ppd</entry> <entry>newer Epson Stylus Color printers </entry> </row> + + <row><entry>stphoto.ppd</entry> <entry>older Epson Stylus Photo printers </entry> </row> + + <row><entry>stphoto2.ppd</entry> <entry>newer Epson Stylus Photo printers </entry> </row> + + <row><entry>laserjet.ppd</entry> <entry>all PCL printers </entry> </row> + + </tbody> + </tgroup> + </table> + + </sect2> + + <sect2> + <title><emphasis>cupsomatic/foomatic-rip</emphasis> Versus <emphasis>Native CUPS</emphasis> Printing</title> + + <para> + <indexterm><primary>cupsomatic</primary></indexterm> + <indexterm><primary>foomatic-rip</primary></indexterm> + Native CUPS rasterization works in two steps: + </para> + + <itemizedlist> + <listitem><para> +<indexterm><primary>pstoraster</primary></indexterm> + First is the <parameter>pstoraster</parameter> step. It uses the special CUPS + <indexterm><primary>ESP</primary><secondary>Ghostscript</secondary></indexterm> + device from ESP Ghostscript 7.05.x as its tool. + </para></listitem> + + <listitem><para> + Second is the <parameter>rasterdriver</parameter> step. It uses various + device-specific filters; there are several vendors who provide good + quality filters for this step. Some are free software, some are + shareware, and some are proprietary. + </para></listitem> + </itemizedlist> + + <para> + Often this produces better quality (and has several more advantages) than other methods. + This is shown in <link linkend="cupsomatic-dia"> the cupsomatic/foomatic Processing Versus Native CUPS + illustration</link>. + </para> + + <figure id="cupsomatic-dia"> + <title>cupsomatic/foomatic Processing Versus Native CUPS.</title> + <imagefile>10small</imagefile> + </figure> + + <para> + One other method is the <parameter>cupsomatic/foomatic-rip</parameter> + way. Note that <parameter>cupsomatic</parameter> is <emphasis>not</emphasis> made by the CUPS + developers. It is an independent contribution to printing development, + made by people from Linuxprinting.org.<footnote><para>See also <ulink + noescape="1" url="http://www.cups.org/cups-help.html">http://www.cups.org/cups-help.html</ulink></para></footnote> + <parameter>cupsomatic</parameter> is no longer developed, maintained, or supported. It now been + replaced by <parameter>foomatic-rip</parameter>. <parameter>foomatic-rip</parameter> is a complete rewrite + of the old <parameter>cupsomatic</parameter> idea, but very much improved and generalized to + other (non-CUPS) spoolers. An upgrade to <parameter>foomatic-rip</parameter> is strongly + advised, especially if you are upgrading to a recent version of CUPS, + too. + </para> + + <para> + <indexterm><primary>cupsomatic</primary></indexterm> + <indexterm><primary>foomatic</primary></indexterm> + Like the old <parameter>cupsomatic</parameter> method, the <parameter>foomatic-rip</parameter> (new) method + from Linuxprinting.org uses the traditional Ghostscript print file processing, doing everything in a single + step. It therefore relies on all the other devices built into Ghostscript. The quality is as good (or bad) as + Ghostscript rendering is in other spoolers. The advantage is that this method supports many printer models not + supported (yet) by the more modern CUPS method. + </para> + + <para> + Of course, you can use both methods side by side on one system (and even for one printer, if you set up + different queues) and find out which works best for you. + </para> + + <para> +<indexterm><primary>cupsomatic</primary></indexterm> +<indexterm><primary>pstoraster</primary></indexterm> +<indexterm><primary>rastertosomething</primary></indexterm> +<indexterm><primary>rasterization</primary></indexterm> +<indexterm><primary>Foomatic/cupsomatic</primary></indexterm> +<indexterm><primary>rendering</primary></indexterm> + <parameter>cupsomatic</parameter> kidnaps the print file after the + <parameter>application/vnd.cups-postscript</parameter> stage and deviates it through the CUPS-external, + systemwide Ghostscript installation. Therefore, the print file bypasses the <parameter>pstoraster</parameter> + filter (and also bypasses the CUPS raster drivers <parameter>rastertosomething</parameter>). After Ghostscript + finished its rasterization, <parameter>cupsomatic</parameter> hands the rendered file directly to the CUPS + backend. <link linkend="cupsomatic-dia">cupsomatic/foomatic Processing Versus Native + CUPS</link>, illustrates the difference between native CUPS rendering and the + <parameter>Foomatic/cupsomatic</parameter> method. + </para> + </sect2> + + <sect2> + <title>Examples for Filtering Chains</title> + + <para> + Here are a few examples of commonly occurring filtering chains to + illustrate the workings of CUPS. + </para> + + <para> +<indexterm><primary>HP JetDirect</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>two-up</primary></indexterm> +<indexterm><primary>duplex</primary></indexterm> + Assume you want to print a PDF file to an HP JetDirect-connected + PostScript printer, but you want to print pages 3-5, 7, and 11-13 + only, and you want to print them <quote>two-up</quote> and <quote>duplex</quote>: + </para> + + <itemizedlist> + <listitem><para>Your print options (page selection as required, two-up, + duplex) are passed to CUPS on the command line.</para></listitem> + + <listitem><para>The (complete) PDF file is sent to CUPS and autotyped as + <parameter>application/pdf</parameter>.</para></listitem> + + <listitem><para>The file therefore must first pass the + <parameter>pdftops</parameter> prefilter, which produces PostScript + MIME type <parameter>application/postscript</parameter> (a preview here + would still show all pages of the original PDF).</para></listitem> + + <listitem><para>The file then passes the <parameter>pstops</parameter> + filter that applies the command-line options: it selects pages + 2-5, 7, and 11-13, creates the imposed layout <quote>two pages on one sheet</quote>, and + inserts the correct <quote>duplex</quote> command (as defined in the printer's + PPD) into the new PostScript file; the file is now of PostScript MIME + type + <parameter>application/vnd.cups-postscript</parameter>.</para></listitem> + + <listitem><para>The file goes to the <parameter>socket</parameter> + backend, which transfers the job to the printers.</para></listitem> + </itemizedlist> + + <para> + The resulting filter chain, therefore, is as shown in <link linkend="pdftosocket">the PDF to socket chain + illustration</link>. + </para> + +<indexterm><primary>pdftosocket</primary></indexterm> + <figure id="pdftosocket"> + <title>PDF to Socket Chain.</title> + <imagefile>pdftosocket</imagefile> + </figure> + + <para> +<indexterm><primary>USB</primary></indexterm> +<indexterm><primary>Epson Stylus</primary></indexterm> +<indexterm><primary>stphoto2.ppd</primary></indexterm> + Assume you want to print the same filter to an USB-connected Epson Stylus Photo Printer installed with the CUPS + <filename>stphoto2.ppd</filename>. The first few filtering stages are nearly the same: + </para> + + <itemizedlist> + <listitem><para> + Your print options (page selection as required, two-up, + duplex) are passed to CUPS on the command line. + </para></listitem> + + <listitem><para> + The (complete) PDF file is sent to CUPS and autotyped as + <parameter>application/pdf</parameter>. + </para></listitem> + + <listitem><para> +<indexterm><primary>pdftops</primary></indexterm> +<indexterm><primary>PDF</primary></indexterm> + The file must first pass the <parameter>pdftops</parameter> prefilter, which produces PostScript + MIME type <parameter>application/postscript</parameter> (a preview here would still show all + pages of the original PDF). + </para></listitem> + + <listitem><para> +<indexterm><primary>pstops</primary></indexterm> +<indexterm><primary>duplex printing</primary></indexterm> + The file then passes the <quote>pstops</quote> filter that applies + the command-line options: it selects the pages 2-5, 7, and 11-13, + creates the imposed layout <quote>two pages on one sheet,</quote> and inserts the + correct <quote>duplex</quote> command (oops &smbmdash; this printer and PPD + do not support duplex printing at all, so this option will + be ignored) into the new PostScript file; the file is now of PostScript + MIME type <parameter>application/vnd.cups-postscript</parameter>. + </para></listitem> + + <listitem><para> + The file then passes the <parameter>pstoraster</parameter> stage and becomes MIME type + <parameter>application/cups-raster</parameter>. + </para></listitem> + + <listitem><para> +<indexterm><primary>rastertoepson</primary></indexterm> + Finally, the <parameter>rastertoepson</parameter> filter + does its work (as indicated in the printer's PPD), creating the + printer-specific raster data and embedding any user-selected + print options into the print data stream. + </para></listitem> + + <listitem><para> + The file goes to the <parameter>usb</parameter> backend, which transfers the job to the printers. + </para></listitem> + </itemizedlist> + + <para> + The resulting filter chain therefore is as shown in <link linkend="pdftoepsonusb">the PDF to USB Chain + illustration</link>. + </para> + + <figure id="pdftoepsonusb"> + <title>PDF to USB Chain.</title> + <imagefile>pdftoepsonusb</imagefile> + </figure> + </sect2> + + <sect2> + <title>Sources of CUPS Drivers/PPDs</title> + + <para> + On the Internet you can now find many thousands of CUPS-PPD files + (with their companion filters), in many national languages + supporting more than 1,000 non-PostScript models. + </para> + + <itemizedlist> + <indexterm><primary>ESP</primary><secondary>Print Pro</secondary></indexterm> + <indexterm><primary>PrintPro</primary><see>ESP Print Pro</see></indexterm> + <listitem><para> + <ulink url="http://www.easysw.com/printpro/">ESP PrintPro</ulink> + (commercial, non-free) is packaged with more than 3,000 PPDs, ready for + successful use <quote>out of the box</quote> on Linux, Mac OS X, IBM-AIX, + HP-UX, Sun-Solaris, SGI-IRIX, Compaq Tru64, Digital UNIX, and + other commercial Unices (it is written by the CUPS developers + themselves and its sales help finance the further development of + CUPS, as they feed their creators). + </para></listitem> + + <listitem><para> + The <ulink url="http://gimp-print.sourceforge.net/">Gimp-Print Project</ulink> + (GPL, free software) provides around 140 PPDs (supporting nearly 400 printers, many driven + to photo quality output), to be used alongside the Gimp-Print CUPS filters. + </para></listitem> + + <listitem><para> + <ulink url="http://www.turboprint.de/english.html/">TurboPrint </ulink> (shareware, non-free) supports + roughly the same number of printers in excellent quality. + </para></listitem> + + <listitem><para> + <ulink url="http://www-124.ibm.com/developerworks/oss/linux/projects/omni/">OMNI </ulink> + (LPGL, free) is a package made by IBM, now containing support for more + than 400 printers, stemming from the inheritance of IBM OS/2 know-how + ported over to Linux (CUPS support is in a beta stage at present). + </para></listitem> + + <listitem><para> + <ulink url="http://hpinkjet.sourceforge.net/">HPIJS </ulink> (BSD-style licenses, free) + supports approximately 150 of HP's own printers and also provides + excellent print quality now (currently available only via the Foomatic path). + </para></listitem> + + <listitem><para> + <ulink url="http://www.linuxprinting.org/">Foomatic/cupsomatic </ulink> + (LPGL, free) from Linuxprinting.org provide PPDs for practically every Ghostscript + filter known to the world (including Omni, Gimp-Print, and HPIJS). + </para></listitem> + </itemizedlist> + + </sect2> + + <sect2> + <title>Printing with Interface Scripts</title> + + <para> +<indexterm><primary>PCL</primary></indexterm> +<indexterm><primary>lpadmin</primary></indexterm> + CUPS also supports the use of <quote>interface scripts</quote> as known from + System V AT&T printing systems. These are often used for PCL + printers, from applications that generate PCL print jobs. Interface + scripts are specific to printer models. They have a role similar to + PPDs for PostScript printers. Interface scripts may inject the Escape + sequences as required into the print data stream if the user, for example, selects + a certain paper tray, or changes paper orientation, or uses A3 + paper. Interface scripts are practically unknown in the Linux + realm. On HP-UX platforms they are more often used. You can use any + working interface script on CUPS too. Just install the printer with + the <command>-i</command> option: +<screen> +&rootprompt;<userinput>lpadmin -p pclprinter -v socket://11.12.13.14:9100 \ + -i /path/to/interface-script</userinput> +</screen></para> + + <para> + Interface scripts might be the <quote>unknown animal</quote> to many. However, + with CUPS they provide the easiest way to plug in your own custom-written filtering + script or program into one specific print queue (some information about the traditional + use of interface scripts is found at + <ulink noescape="1" url="http://playground.sun.com/printing/documentation/interface.html"> + http://playground.sun.com/printing/documentation/interface.html</ulink>). + </para> + </sect2> +</sect1> + +<sect1> +<title>Network Printing (Purely Windows)</title> + +<para> +Network printing covers a lot of ground. To understand what exactly +goes on with Samba when it is printing on behalf of its Windows +clients, let's first look at a <quote>purely Windows</quote> setup: Windows clients +with a Windows NT print server. +</para> + +<sect2> +<title>From Windows Clients to an NT Print Server</title> + +<para> +Windows clients printing to an NT-based print server have two +options. They may: +<indexterm><primary>GDI</primary></indexterm> +<indexterm><primary>EMF</primary></indexterm> +</para> + + +<itemizedlist> + <listitem><para>Execute the driver locally and render the GDI output + (EMF) into the printer-specific format on their own. + </para></listitem> + + <listitem><para>Send the GDI output (EMF) to the server, where the + driver is executed to render the printer-specific output. + </para></listitem> +</itemizedlist> + +<para> +Both print paths are shown in the flowcharts in <link linkend="small11"> +Print Driver Execution on the Client</link>, and +<link linkend="small12">Print Driver Execution on the Server</link>. +</para> +</sect2> + +<sect2> +<title>Driver Execution on the Client</title> + +<para> +In the first case, the print server must spool the file as raw, meaning it shouldn't touch the job file and try +to convert it in any way. This is what a traditional UNIX-based print server can do too, and at a better +performance and more reliably than an NT print server. This is what most Samba administrators probably are +familiar with. One advantage of this setup is that this <quote>spooling-only</quote> print server may be used +even if no driver(s) for UNIX is available. It is sufficient to have the Windows client drivers available and +installed on the clients. This is illustrated in <link linkend="small11">the Print Driver Execution on the +Client diagram</link>. +</para> + +<figure id="small11"> + <title>Print Driver Execution on the Client.</title> + <imagefile>11small</imagefile> +</figure> + +</sect2> + +<sect2> +<title>Driver Execution on the Server</title> + + +<para> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>PCL</primary></indexterm> +<indexterm><primary>ESC/P</primary></indexterm> +<indexterm><primary>EMF</primary></indexterm> +<indexterm><primary>GDI</primary></indexterm> +The other path executes the printer driver on the server. The client transfers print files in EMF format to +the server. The server uses the PostScript, PCL, ESC/P, or other driver to convert the EMF file into the +printer-specific language. It is not possible for UNIX to do the same. Currently, there is no program or +method to convert a Windows client's GDI output on a UNIX server into something a printer could understand. +This is illustrated in <link linkend="small12">the Print Driver Execution on the Server diagram</link>. +</para> + + <figure id="small12"> + <title>Print Driver Execution on the Server.</title> + <imagefile>12small</imagefile> + </figure> + +<para> +However, something similar is possible with CUPS, so read on. +</para> +</sect2> +</sect1> + +<sect1> +<title>Network Printing (Windows Clients and UNIX/Samba Print +Servers)</title> + +<para> +Since UNIX print servers <emphasis>cannot</emphasis> execute the Win32 +program code on their platform, the picture is somewhat +different. However, this does not limit your options all that +much. On the contrary, you may have a way here to implement printing +features that are not possible otherwise. +</para> + +<sect2> +<title>From Windows Clients to a CUPS/Samba Print Server</title> + +<para> +Here is a simple recipe showing how you can take advantage of CUPS's +powerful features for the benefit of your Windows network printing +clients: +</para> + +<itemizedlist> + <listitem><para>Let the Windows clients send PostScript to the CUPS + server.</para></listitem> + + <listitem><para>Let the CUPS server render the PostScript into device-specific raster format.</para></listitem> +</itemizedlist> + +<para> +This requires the clients to use a PostScript driver (even if the +printer is a non-PostScript model. It also requires that you have a +driver on the CUPS server. +</para> + +<para> +First, to enable CUPS-based printing through Samba, the following options should be set in your &smb.conf; +file <parameter>[global]</parameter> section: +</para> + +<smbconfblock> +<smbconfoption name="printing">cups</smbconfoption> +<smbconfoption name="printcap">cups</smbconfoption> +</smbconfblock> + +<para> +When these parameters are specified, all manually set print directives (like <smbconfoption name="print +command"/> or <smbconfoption name="lppause command"/>) in &smb.conf; (as well as in Samba itself) will be +ignored. Instead, Samba will directly interface with CUPS through its application program interface (API), as +long as Samba has been compiled with CUPS library (libcups) support. If Samba has not been compiled with CUPS +support, and if no other print commands are set up, then printing will use the <emphasis>System V</emphasis> +AT&T command set, with the -oraw option automatically passing through (if you want your own defined print +commands to work with a Samba server that has CUPS support compiled in, simply use <smbconfoption +name="classicalprinting">sysv</smbconfoption>). This is illustrated in <link linkend="13small">the Printing via +CUPS/Samba Server diagram</link>. +</para> + + <figure id="13small"> + <title>Printing via CUPS/Samba Server.</title> + <imagefile>13small</imagefile> + </figure> +</sect2> + +<sect2> +<title>Samba Receiving Job-Files and Passing Them to CUPS</title> + +<para> +Samba <emphasis>must</emphasis> use its own spool directory (it is set by a line similar to <smbconfoption +name="path">/var/spool/samba</smbconfoption>, in the <smbconfsection name="[printers]"/> or <smbconfsection +name="[printername]"/> section of &smb.conf;). Samba receives the job in its own spool space and passes it +into the spool directory of CUPS (the CUPS spool directory is set by the <parameter>RequestRoot</parameter> +directive in a line that defaults to <parameter>RequestRoot /var/spool/cups</parameter>). CUPS checks the +access rights of its spool directory and resets it to healthy values with every restart. We have seen quite a +few people who used a common spooling space for Samba and CUPS, and struggled for weeks with this +<quote>problem.</quote> +</para> + +<para> +A Windows user authenticates only to Samba (by whatever means is +configured). If Samba runs on the same host as CUPS, you only need to +allow <quote>localhost</quote> to print. If it runs on different machines, you +need to make sure the Samba host gets access to printing on CUPS. +</para> +</sect2> +</sect1> + +<sect1> +<title>Network PostScript RIP</title> + +<para> +This section discusses the use of CUPS filters on the server &smbmdash; configuration where +clients make use of a PostScript driver with CUPS-PPDs. +</para> + + +<para> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>PCL</primary></indexterm> +<indexterm><primary>PJL</primary></indexterm> +PPDs can control all print device options. They are usually provided by the manufacturer &smbmdash; if you own +a PostScript printer, that is. PPD files are always a component of PostScript printer drivers on MS Windows or +Apple Mac OS systems. They are ASCII files containing user-selectable print options, mapped to appropriate +PostScript, PCL, or PJL commands for the target printer. Printer driver GUI dialogs translate these options +<quote>on the fly</quote> into buttons and drop-down lists for the user to select. +</para> + +<para> +CUPS can load, without any conversions, the PPD file from any Windows (NT is recommended) PostScript driver +and handle the options. There is a Web browser interface to the print options (select <ulink noescape="1" +url="http://localhost:631/printers/">http://localhost:631/printers/</ulink> and click on one +<guibutton>Configure Printer</guibutton> button to see it) or a command-line interface (see <command>man +lpoptions</command> or see if you have <command>lphelp</command> on your system). There are also some +different GUI front-ends on Linux/UNIX, which can present PPD options to users. PPD options are normally meant +to be evaluated by the PostScript RIP on the real PostScript printer. +</para> + +<sect2> +<title>PPDs for Non-PS Printers on UNIX</title> + + +<para> +<indexterm><primary>PPD</primary></indexterm> +CUPS does not limit itself to <quote>real</quote> PostScript printers in its use of PPDs. The CUPS developers +have extended the scope of the PPD concept to also describe available device and driver options for +non-PostScript printers through CUPS-PPDs. +</para> + +<para> +This is logical, because CUPS includes a fully featured PostScript interpreter (RIP). This RIP is based on +Ghostscript. It can process all received PostScript (and additionally many other file formats) from clients. +All CUPS-PPDs geared to non-PostScript printers contain an additional line, starting with the keyword +<parameter>*cupsFilter</parameter>. This line tells the CUPS print system which printer-specific filter to use +for the interpretation of the supplied PostScript. Thus CUPS lets all its printers appear as PostScript +devices to its clients, because it can act as a PostScript RIP for those printers, processing the received +PostScript code into a proper raster print format. +</para> +</sect2> + +<sect2> +<title>PPDs for Non-PS Printers on Windows</title> + +<para> +<indexterm><primary>PPD</primary></indexterm> +CUPS-PPDs can also be used on Windows clients, on top of a <quote>core</quote> PostScript driver (now +recommended is the CUPS PostScript Driver for Windows NT/200x/XP; you can also use the Adobe one, with +limitations). This feature enables CUPS to do a few tricks no other spooler can do: +</para> + +<itemizedlist> + <listitem><para> + Act as a networked PostScript RIP handling print files from all client platforms in a uniform way. + </para></listitem> + + <listitem><para> + Act as a central accounting and billing server, since all files are passed through the pstops filter and are therefore + logged in the CUPS <filename>page_log</filename> file. <emphasis>Note:</emphasis> this cannot happen with + <quote>raw</quote> print jobs, which always remain unfiltered per definition. + </para></listitem> + + <listitem><para> + Enable clients to consolidate on a single PostScript driver, even for many different target printers. + </para></listitem> +</itemizedlist> + +<para> +Using CUPS PPDs on Windows clients enables them to control all print job settings just as a UNIX client can do. +</para> +</sect2> +</sect1> + +<sect1> +<title>Windows Terminal Servers (WTS) as CUPS Clients</title> + +<para> +This setup may be of special interest to people experiencing major problems in WTS environments. WTS often +need a multitude of non-PostScript drivers installed to run their clients' variety of different printer +models. This often imposes the price of much increased instability. +</para> + +<sect2> +<title>Printer Drivers Running in <quote>Kernel Mode</quote> Cause Many +Problems</title> + +<para> +Windows NT printer drivers, which run in <quote>kernel mode</quote>, introduce a high risk for the stability +of the system if the driver is not really stable and well-tested. And there are a lot of bad drivers out +there! Especially notorious is the example of the PCL printer driver that had an additional sound module +running to notify users via soundcard of their finished jobs. Do I need to say that this one was also reliably +causing <quote>blue screens of death</quote> on a regular basis? +</para> + +<para> +PostScript drivers are generally well-tested. They are not known to cause any problems, even though they also +run in kernel mode. This might be because until now there have been only two different PostScript drivers: the +one from Adobe and the one from Microsoft. Both are well-tested and are as stable as you can imagine on +Windows. The CUPS driver is derived from the Microsoft one. +</para> +</sect2> + +<sect2> +<title>Workarounds Impose Heavy Limitations</title> + +<para> +In an attempt to work around problems, site administrators have resorted to restricting the +allowed drivers installed on their WTS to one generic PCL and one PostScript driver. This, however, restricts +the number of printer options available for clients to use. Often they can't get out more than simplex +prints from one standard paper tray, while their devices could do much better if driven by a different driver! +</para> +</sect2> + +<sect2> +<title>CUPS: A <quote>Magical Stone</quote>?</title> + +<para> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +Using a PostScript driver, enabled with a CUPS-PPD, seems to be a very elegant way to overcome all these +shortcomings. There are, depending on the version of Windows OS you use, up to three different PostScript +drivers now available: Adobe, Microsoft, and CUPS PostScript drivers. None of them is known to cause major +stability problems on WTS (even if used with many different PPDs). The clients will be able to (again) choose +paper trays, duplex printing, and other settings. However, there is a certain price for this too: a CUPS +server acting as a PostScript RIP for its clients requires more CPU and RAM than when just acting as a +<quote>raw spooling</quote> device. Plus, this setup is not yet widely tested, although the first feedbacks +look very promising. +</para> +</sect2> + +<sect2> +<title>PostScript Drivers with No Major Problems, Even in Kernel +Mode</title> + +<para> +<indexterm><primary>DDK</primary></indexterm> +<indexterm><primary>W32X86</primary></indexterm> +<indexterm><primary>PostScript</primary></indexterm> +<indexterm><primary>Visual Studio</primary></indexterm> +<indexterm><primary>Microsoft driver</primary></indexterm> +<indexterm><primary>Adobe</primary></indexterm> +More recent printer drivers on W200x and XP no longer run in kernel mode (unlike Windows NT). However, both +operating systems can still use the NT drivers, running in kernel mode (you can roughly tell which is which as +the drivers in subdirectory <quote>2</quote> of <quote>W32X86</quote> are <quote>old</quote> ones). As was +said before, the Adobe as well as the Microsoft PostScript drivers are not known to cause any stability +problems. The CUPS driver is derived from the Microsoft one. There is a simple reason for this: the MS DDK +(Device Development Kit) for Windows NT (which used to be available at no cost to licensees of Visual Studio) +includes the source code of the Microsoft driver, and licensees of Visual Studio are allowed to use and modify +it for their own driver development efforts. This is what the CUPS people have done. The license does not +allow them to publish the whole of the source code. However, they have released the <quote>diff</quote> under +the GPL, and if you are the owner of an <quote>MS DDK for Windows NT,</quote> you can check the driver +yourself. +</para> +</sect2> +</sect1> + +<sect1> +<title>Configuring CUPS for Driver Download</title> + +<para> +As we have said before, all previously known methods to prepare client printer drivers on the Samba server for +download and Point'n'Print convenience of Windows workstations are working with CUPS, too. These methods were +described in <link linkend="classicalprinting">Classical Printing</link>. In reality, this is a pure Samba +business and relates only to the Samba-Windows client relationship. +</para> + +<sect2> +<title><emphasis>cupsaddsmb</emphasis>: The Unknown Utility</title> + + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +The <parameter>cupsaddsmb</parameter> utility (shipped with all current CUPS versions) is an alternative +method to transfer printer drivers into the Samba <smbconfsection name="[print$]"/> share. Remember, this +share is where clients expect drivers deposited and set up for download and installation. It makes the sharing +of any (or all) installed CUPS printers quite easy. <command>cupsaddsmb</command> can use the Adobe PostScript +driver as well as the newly developed CUPS PostScript driver for Windows NT/200x/XP. +<parameter>cupsaddsmb</parameter> does <emphasis>not</emphasis> work with arbitrary vendor printer drivers, +but only with the <emphasis>exact</emphasis> driver files that are named in its man page. +</para> + +<para> +The CUPS printer driver is available from the CUPS download site. Its package name is +<filename>cups-samba-[version].tar.gz</filename>. It is preferred over the Adobe drivers because it has a +number of advantages: +</para> + +<itemizedlist> + <listitem><para>It supports a much more accurate page accounting.</para></listitem> + + <listitem><para>It supports banner pages and page labels on all printers.</para></listitem> + + <listitem><para>It supports the setting of a number of job IPP attributes + (such as job priority, page label, and job billing).</para></listitem> +</itemizedlist> + +<para> +However, currently only Windows NT, 2000, and XP are supported by the +CUPS drivers. You will also need to get the respective part of the Adobe driver +if you need to support Windows 95, 98, and Me clients. +</para> +</sect2> + +<sect2> +<title>Prepare Your &smb.conf; for <command>cupsaddsmb</command></title> + +<para> +Prior to running <command>cupsaddsmb</command>, you need the settings in +&smb.conf; as shown in <link linkend="cupsadd-ex">the &smb.conf; for cupsaddsmb Usage</link>. +</para> + +<example id="cupsadd-ex"> +<title>smb.conf for cupsaddsmb Usage</title> +<smbconfblock> +<smbconfsection name="[global]"/> +<smbconfoption name="load printers">yes</smbconfoption> +<smbconfoption name="printing">cups</smbconfoption> +<smbconfoption name="printcap name">cups</smbconfoption> + +<smbconfsection name="[printers]"/> +<smbconfoption name="comment">All Printers</smbconfoption> +<smbconfoption name="path">/var/spool/samba</smbconfoption> +<smbconfoption name="browseable">no</smbconfoption> +<smbconfoption name="public">yes</smbconfoption> +<smbconfcomment>setting depends on your requirements</smbconfcomment> +<smbconfoption name="guest ok">yes</smbconfoption> +<smbconfoption name="writable">no</smbconfoption> +<smbconfoption name="printable">yes</smbconfoption> +<smbconfoption name="printer admin">root</smbconfoption> + <smbconfsection name="[print$]"/> +<smbconfoption name="comment">Printer Drivers</smbconfoption> +<smbconfoption name="path">/etc/samba/drivers</smbconfoption> +<smbconfoption name="browseable">yes</smbconfoption> +<smbconfoption name="guest ok">no</smbconfoption> +<smbconfoption name="read only">yes</smbconfoption> +<smbconfoption name="write list">root</smbconfoption> +</smbconfblock> +</example> +</sect2> + +<sect2> +<title>CUPS <quote>PostScript Driver for Windows NT/200x/XP</quote></title> + +<para> +<indexterm><primary>PostScript</primary></indexterm> +CUPS users may get the exact same package from <ulink noescape="1" +url="http://www.cups.org/software.html">http://www.cups.org/software.html</ulink>. It is a separate package +from the CUPS-based software files, tagged as CUPS 1.1.x Windows NT/200x/XP Printer Driver for Samba (tar.gz, +192k). The filename to download is <filename>cups-samba-1.1.x.tar.gz</filename>. Upon untar and unzipping, it +will reveal these files: +<screen> +&rootprompt;<userinput>tar xvzf cups-samba-1.1.19.tar.gz</userinput> +cups-samba.install +cups-samba.license +cups-samba.readme +cups-samba.remove +cups-samba.ss +</screen></para> + +<para> +<indexterm><primary>ESP</primary><secondary>meta packager</secondary></indexterm> +<indexterm><primary>EPM</primary><see>ESP meta packager</see></indexterm> +These have been packaged with the ESP meta-packager software EPM. The <filename>*.install</filename> and +<filename>*.remove</filename> files are simple shell scripts, which untar the <filename>*.ss</filename> (the +<filename>*.ss</filename> is nothing else but a tar archive, which can be untarred by <quote>tar</quote> too). +Then it puts the content into <filename>/usr/share/cups/drivers/</filename>. This content includes three +files: +<screen> +&rootprompt;<userinput>tar tv cups-samba.ss</userinput> +cupsdrvr.dll +cupsui.dll +cups.hlp +</screen></para> + +<para> +The <parameter>cups-samba.install</parameter> shell scripts are easy to +handle: +<screen> +&rootprompt;<userinput>./cups-samba.install</userinput> +[....] +Installing software... +Updating file permissions... +Running post-install commands... +Installation is complete. +</screen></para> + +<para> +The script should automatically put the driver files into the +<filename>/usr/share/cups/drivers/</filename> directory: +<screen> +&rootprompt;<userinput>cp /usr/share/drivers/cups.hlp /usr/share/cups/drivers/</userinput> +</screen></para> + +<warning><para> +Due to a bug, one recent CUPS release puts the <filename>cups.hlp</filename> driver file +into<filename>/usr/share/drivers/</filename> instead of <filename>/usr/share/cups/drivers/</filename>. To work +around this, copy/move the file (after running the <command>./cups-samba.install</command> script) manually to +the correct place. +</para></warning> + +<para> +<indexterm><primary>DDK</primary></indexterm> +This new CUPS PostScript driver is currently binary only, but free of charge. No complete source code is +provided (yet). The reason is that it has been developed with the help of the Microsoft DDK and compiled with +Microsoft Visual Studio 6. Driver developers are not allowed to distribute the whole of the source code as +free software. However, CUPS developers released the <quote>diff</quote> in source code under the GPL, so +anybody with a license for Visual Studio and a DDK will be able to compile for himself or herself. +</para> +</sect2> + +<sect2> +<title>Recognizing Different Driver Files</title> + +<para> +The CUPS drivers do not support the older Windows 95/98/Me, but only the Windows NT/2000/XP client. +</para> + +<para>Windows NT, 2000, and XP are supported by:</para> + +<itemizedlist> + <listitem><para>cups.hlp</para></listitem> + <listitem><para>cupsdrvr.dll</para></listitem> + <listitem><para>cupsui.dll</para></listitem> +</itemizedlist> + +<para> +Adobe drivers are available for the older Windows 95/98/Me as well as +for Windows NT/2000/XP clients. The set of files is different from the +different platforms. +</para> + +<para>Windows 95, 98, and ME are supported by:</para> + +<itemizedlist> + <listitem><para>ADFONTS.MFM</para></listitem> + <listitem><para>ADOBEPS4.DRV</para></listitem> + <listitem><para>ADOBEPS4.HLP</para></listitem> + <listitem><para>DEFPRTR2.PPD</para></listitem> + <listitem><para>ICONLIB.DLL</para></listitem> + <listitem><para>PSMON.DLL</para></listitem> +</itemizedlist> + +<para>Windows NT, 2000, and XP are supported by:</para> + +<itemizedlist> + <listitem><para>ADOBEPS5.DLL</para></listitem> + <listitem><para>ADOBEPSU.DLL</para></listitem> + <listitem><para>ADOBEPSU.HLP</para></listitem> +</itemizedlist> + +<note><para> +<indexterm><primary>Adobe driver files</primary></indexterm> +If both the Adobe driver files and the CUPS driver files for the support of Windows NT/200x/XP are presently +installed on the server, the Adobe files will be ignored and the CUPS files will be used. If you prefer +&smbmdash; for whatever reason &smbmdash; to use Adobe-only drivers, move away the three CUPS driver files. +The Windows 9x/Me clients use the Adobe drivers in any case. +</para></note> +</sect2> + +<sect2> +<title>Acquiring the Adobe Driver Files</title> + +<para> +Acquiring the Adobe driver files seems to be unexpectedly difficult for many users. They are not available on +the Adobe Web site as single files, and the self-extracting and/or self-installing Windows-.exe is not easy to +locate either. You probably need to use the included native installer and run the installation process on one +client once. This will install the drivers (and one generic PostScript printer) locally on the client. When +they are installed, share the generic PostScript printer. After this, the client's <smbconfsection +name="[print$]"/> share holds the Adobe files, which you can get with smbclient from the CUPS host. +</para> +</sect2> + +<sect2> +<title>ESP Print Pro PostScript Driver for Windows NT/200x/XP</title> + +<para> +<indexterm><primary>ESP</primary><secondary>Print Pro</secondary></indexterm> +Users of the ESP Print Pro software are able to install the ESP print drivers package as an alternative to the +Adobe PostScript drivers. To do so, retrieve the driver files from the normal download area of the ESP Print +Pro software at <ulink noescape="1" url="http://www.easysw.com/software.html">Easy Software</ulink> web site. +You need to locate the link labeled <quote>SAMBA</quote> among the <guilabel>Download Printer Drivers for ESP +Print Pro 4.x</guilabel> area and download the package. Once installed, you can prepare any driver by simply +highlighting the printer in the Printer Manager GUI and selecting <guilabel>Export Driver...</guilabel> from +the menu. Of course, you need to have prepared Samba beforehand to handle the driver files; that is, set up +the <smbconfsection name="[print$]"/> share, and so on. The ESP Print Pro package includes the CUPS driver +files as well as a (licensed) set of Adobe drivers for the Windows 95/98/Me client family. +</para> +</sect2> + +<sect2> +<title>Caveats to Be Considered</title> + + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +<indexterm><primary>cups.hlp</primary></indexterm> +<indexterm><primary>WIN40</primary></indexterm> +<indexterm><primary>W32X86</primary></indexterm> +Once you have run the install script (and possibly manually moved the <filename>cups.hlp</filename> file to +<filename>/usr/share/cups/drivers/</filename>), the driver is ready to be put into Samba's <smbconfsection +name="[print$]"/> share (which often maps to <filename>/etc/samba/drivers/</filename> and contains a +subdirectory tree with <emphasis>WIN40</emphasis> and <emphasis>W32X86</emphasis> branches). You do this by +running <command>cupsaddsmb</command> (see also <command>man cupsaddsmb</command> for CUPS since release +1.1.16). +</para> + +<tip><para> +<indexterm><primary>Single Sign-On</primary></indexterm> +<indexterm><primary>Domain Controller</primary></indexterm> +You may need to put root into the smbpasswd file by running <command>smbpasswd</command>; this is especially +important if you should run this whole procedure for the first time and are not working in an environment +where everything is configured for <emphasis>single sign-on</emphasis> to a Windows Domain Controller. +</para></tip> + +<para> +Once the driver files are in the <smbconfsection name="[print$]"/> share and are initialized, they are ready +to be downloaded and installed by the Windows NT/200x/XP clients. +</para> + +<note><para> +Win 9x/Me clients will not work with the CUPS PostScript driver. For these you still need to use the +<filename>ADOBE*.*</filename> drivers, as previously stated. +</para></note> + +<note> +<para> +It is not harmful if you still have the <filename>ADOBE*.*</filename> driver files from previous installations +in the <filename>/usr/share/cups/drivers/</filename> directory. The new <command>cupsaddsmb</command> (from +1.1.16) will automatically prefer its own drivers if it finds both. +</para></note> + +<note><para> +<indexterm><primary>"Printers" folder</primary></indexterm> +<indexterm><primary>Adobe PostScript</primary></indexterm> +Should your Windows clients have had the old <filename>ADOBE*.*</filename> files for the Adobe PostScript +driver installed, the download and installation of the new CUPS PostScript driver for Windows NT/200x/XP will +fail at first. You need to wipe the old driver from the clients first. It is not enough to +<quote>delete</quote> the printer, because the driver files will still be kept by the clients and re-used if +you try to re-install the printer. To really get rid of the Adobe driver files on the clients, open the +<guilabel>Printers</guilabel> folder (possibly via <guilabel>Start -> Settings -> Control Panel -> +Printers</guilabel>), right-click on the folder background, and select <guimenuitem>Server +Properties</guimenuitem>. When the new dialog opens, select the <guilabel>Drivers</guilabel> tab. On the list +select the driver you want to delete and click the <guilabel>Delete</guilabel> button. This will only work if +there is not one single printer left that uses that particular driver. You need to <quote>delete</quote> all +printers using this driver in the <guilabel>Printers</guilabel> folder first. You will need Administrator +privileges to do this. +</para></note> + +<note><para> +<indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> +<indexterm><primary>CUPS PostScript</primary></indexterm> +Once you have successfully downloaded the CUPS PostScript driver to a client, you can easily switch all +printers to this one by proceeding as described in <link linkend="classicalprinting">Classical Printing +Support</link>. Either change a driver for an existing printer by running the <guilabel>Printer +Properties</guilabel> dialog, or use <command>rpcclient</command> with the <command>setdriver</command> +subcommand. +</para></note> +</sect2> + +<sect2> +<title>Windows CUPS PostScript Driver Versus Adobe Driver</title> + +<para> +Are you interested in a comparison between the CUPS and the Adobe PostScript drivers? For our purposes, these +are the most important items that weigh in favor of CUPS: +</para> + +<itemizedlist> + <listitem><para>No hassle with the Adobe EULA.</para></listitem> + + <listitem><para>No hassle with the question, <quote>Where do I + get the ADOBE*.* driver files?</quote></para></listitem> + + <listitem><para> + <indexterm><primary>PJL</primary></indexterm> + The Adobe drivers (on request of the printer PPD associated with them) often put a PJL header in front of the + main PostScript part of the print file. Thus, the print file starts with <parameter><1B + >%-12345X</parameter> or <parameter><escape>%-12345X</parameter> instead of + <parameter>%!PS</parameter>. This leads to the CUPS daemon autotyping the incoming file as a print-ready file, + not initiating a pass through the <parameter>pstops</parameter> filter (to speak more technically, it is not + regarded as the generic MIME-type <indexterm><primary>application/postscript</primary></indexterm> + <parameter>application/postscript</parameter>, but as the more special MIME type + <indexterm><primary>application/cups.vnd-postscript</primary></indexterm> + <parameter>application/cups.vnd-postscript</parameter>), which therefore also leads to the page accounting in + <parameter>/var/log/cups/page_log</parameter> not receiving the exact number of pages; instead the dummy page + number of <quote>1</quote> is logged in a standard setup). + </para></listitem> + + <listitem><para>The Adobe driver has more options to misconfigure the +<indexterm><primary>Adobe driver</primary></indexterm> + PostScript generated by it (like setting it inadvertently to + <guilabel>Optimize for Speed</guilabel> instead of + <guilabel>Optimize for Portability</guilabel>, which + could lead to CUPS being unable to process it).</para></listitem> + + <listitem><para>The CUPS PostScript driver output sent by Windows +<indexterm><primary>CUPS PostScript driver</primary></indexterm> + clients to the CUPS server is guaranteed to autotype + as the generic MIME type <parameter>application/postscript</parameter>, + thus passing through the CUPS <parameter>pstops</parameter> filter and logging the + correct number of pages in the <filename>page_log</filename> for + accounting and quota purposes.</para></listitem> + + <listitem><para> + <indexterm><primary>banner pages</primary></indexterm> + The CUPS PostScript driver supports the sending of additional standard (IPP) print options by Windows + NT/200x/XP clients. Such additional print options are naming the CUPS standard <emphasis>banner + pages</emphasis> (or the custom ones, should they be installed at the time of driver download), using the CUPS + page-label option, setting a job priority, and setting the scheduled time of printing (with the option to + support additional useful IPP job attributes in the future). + </para></listitem> + + <listitem><para>The CUPS PostScript driver supports the inclusion of + the new <parameter>*cupsJobTicket</parameter> comments at the + beginning of the PostScript file (which could be used in the future + for all sorts of beneficial extensions on the CUPS side, but which will + not disturb any other applications because they will regard it as a comment + and simply ignore it).</para></listitem> + + <listitem><para>The CUPS PostScript driver will be the heart of the + fully fledged CUPS IPP client for Windows NT/200x/XP to be released soon + (probably alongside the first beta release for CUPS 1.2).</para></listitem> +</itemizedlist> + +</sect2> + +<sect2> +<title>Run cupsaddsmb (Quiet Mode)</title> + + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +<indexterm><primary>point 'n' print</primary></indexterm> +The <command>cupsaddsmb</command> command copies the needed files into your <smbconfsection name="[print$]"/> +share. Additionally, the PPD associated with this printer is copied from <filename>/etc/cups/ppd/</filename> +to <smbconfsection name="[print$]"/>. There the files wait for convenient Windows client installations via +Point'n'Print. Before we can run the command successfully, we need to be sure that we can authenticate toward +Samba. If you have a small network, you are probably using user-level security (<smbconfoption +name="security">user</smbconfoption>). +</para> + +<para> +Here is an example of a successfully run <command>cupsaddsmb</command> command: +<indexterm><primary>banner pages</primary></indexterm> +<indexterm><primary>cupsaddsmb</primary></indexterm> +<screen> +&rootprompt;<userinput>cupsaddsmb -U root infotec_IS2027</userinput> +Password for root required to access localhost via Samba: <userinput>['secret']</userinput> +</screen></para> + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +To share <emphasis>all</emphasis> printers and drivers, use the +<option>-a</option> parameter instead of a printer name. Since +<command>cupsaddsmb</command> <quote>exports</quote> the printer drivers to Samba, it should be +obvious that it only works for queues with a CUPS driver associated. +</para> +</sect2> + +<sect2> +<title>Run cupsaddsmb with Verbose Output</title> + + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +Probably you want to see what's going on. Use the +<option>-v</option> parameter to get a more verbose output. The +output below was edited for better readability: all <quote>\</quote> at the end of +a line indicate that I inserted an artificial line break plus some +indentation here: +<indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> +<screen> +&rootprompt;<userinput>cupsaddsmb -U root -v infotec_2105</userinput> +Password for root required to access localhost via &example.server.samba;: +Running command: smbclient //localhost/print\$ -N -U'root%secret' \ + -c 'mkdir W32X86; \ + put /var/spool/cups/tmp/3e98bf2d333b5 W32X86/infotec_2105.ppd; \ + put /usr/share/cups/drivers/cupsdrvr.dll W32X86/cupsdrvr.dll; \ + put /usr/share/cups/drivers/cupsui.dll W32X86/cupsui.dll; \ + put /usr/share/cups/drivers/cups.hlp W32X86/cups.hlp' +added interface ip=10.160.51.60 bcast=10.160.51.255 nmask=255.255.252.0 +Domain=[CUPS-PRINT] OS=[UNIX] Server=[Samba 2.2.7a] +NT_STATUS_OBJECT_NAME_COLLISION making remote directory \W32X86 +putting file /var/spool/cups/tmp/3e98bf2d333b5 as \W32X86/infotec_2105.ppd +putting file /usr/share/cups/drivers/cupsdrvr.dll as \W32X86/cupsdrvr.dll +putting file /usr/share/cups/drivers/cupsui.dll as \W32X86/cupsui.dll +putting file /usr/share/cups/drivers/cups.hlp as \W32X86/cups.hlp + +Running command: rpcclient localhost -N -U'root%secret' + -c 'adddriver "Windows NT x86" \ + "infotec_2105:cupsdrvr.dll:infotec_2105.ppd:cupsui.dll:cups.hlp:NULL: \ + RAW:NULL"' +cmd = adddriver "Windows NT x86" \ + "infotec_2105:cupsdrvr.dll:infotec_2105.ppd:cupsui.dll:cups.hlp:NULL: \ + RAW:NULL" +Printer Driver infotec_2105 successfully installed. + +Running command: smbclient //localhost/print\$ -N -U'root%secret' \ +-c 'mkdir WIN40; \ + put /var/spool/cups/tmp/3e98bf2d333b5 WIN40/infotec_2105.PPD; \ + put /usr/share/cups/drivers/ADFONTS.MFM WIN40/ADFONTS.MFM; \ + put /usr/share/cups/drivers/ADOBEPS4.DRV WIN40/ADOBEPS4.DRV; \ + put /usr/share/cups/drivers/ADOBEPS4.HLP WIN40/ADOBEPS4.HLP; \ + put /usr/share/cups/drivers/DEFPRTR2.PPD WIN40/DEFPRTR2.PPD; \ + put /usr/share/cups/drivers/ICONLIB.DLL WIN40/ICONLIB.DLL; \ + put /usr/share/cups/drivers/PSMON.DLL WIN40/PSMON.DLL;' + added interface ip=10.160.51.60 bcast=10.160.51.255 nmask=255.255.252.0 + Domain=[CUPS-PRINT] OS=[UNIX] Server=[Samba 2.2.7a] + NT_STATUS_OBJECT_NAME_COLLISION making remote directory \WIN40 + putting file /var/spool/cups/tmp/3e98bf2d333b5 as \WIN40/infotec_2105.PPD + putting file /usr/share/cups/drivers/ADFONTS.MFM as \WIN40/ADFONTS.MFM + putting file /usr/share/cups/drivers/ADOBEPS4.DRV as \WIN40/ADOBEPS4.DRV + putting file /usr/share/cups/drivers/ADOBEPS4.HLP as \WIN40/ADOBEPS4.HLP + putting file /usr/share/cups/drivers/DEFPRTR2.PPD as \WIN40/DEFPRTR2.PPD + putting file /usr/share/cups/drivers/ICONLIB.DLL as \WIN40/ICONLIB.DLL + putting file /usr/share/cups/drivers/PSMON.DLL as \WIN40/PSMON.DLL + + Running command: rpcclient localhost -N -U'root%secret' \ + -c 'adddriver "Windows 4.0" \ + "infotec_2105:ADOBEPS4.DRV:infotec_2105.PPD:NULL:ADOBEPS4.HLP: \ + PSMON.DLL:RAW:ADOBEPS4.DRV,infotec_2105.PPD,ADOBEPS4.HLP,PSMON.DLL, \ + ADFONTS.MFM,DEFPRTR2.PPD,ICONLIB.DLL"' + cmd = adddriver "Windows 4.0" "infotec_2105:ADOBEPS4.DRV:\ + infotec_2105.PPD:NULL:ADOBEPS4.HLP:PSMON.DLL:RAW:ADOBEPS4.DRV,\ + infotec_2105.PPD,ADOBEPS4.HLP,PSMON.DLL,ADFONTS.MFM,DEFPRTR2.PPD,\ + ICONLIB.DLL" + Printer Driver infotec_2105 successfully installed. + + Running command: rpcclient localhost -N -U'root%secret' \ + -c 'setdriver infotec_2105 infotec_2105' + cmd = setdriver infotec_2105 infotec_2105 + Successfully set infotec_2105 to driver infotec_2105. +</screen></para> + +<warning><para> +You will see the root password for the Samba account printed on screen. +</para></warning> + +<para> +If you look closely, you'll discover your root password was transferred unencrypted over the wire, so beware! +Also, if you look further, you may discover error messages like NT_STATUS_OBJECT_NAME_COLLISION in the output. +This will occur when the directories WIN40 and W32X86 already existed in the <smbconfsection name="[print$]"/> +driver download share (from a previous driver installation). These are harmless warning messages. +</para> +</sect2> + +<sect2> +<title>Understanding cupsaddsmb</title> + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +What has happened? What did <command>cupsaddsmb</command> do? There are five stages of the procedure: +</para> + +<orderedlist> + <listitem><para> + <indexterm><primary>IPP</primary></indexterm> + Call the CUPS server via IPP and request the driver files and the PPD file for the named printer.</para></listitem> + + <listitem><para>Store the files temporarily in the local TEMPDIR (as defined in <filename>cupsd.conf</filename>).</para></listitem> + + <listitem><para>Connect via smbclient to the Samba server's <smbconfsection name="[print$]"/> share and put the files into the + share's WIN40 (for Windows 9x/Me) and W32X86 (for Windows NT/200x/XP) subdirectories.</para></listitem> + + <listitem><para> + <indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> + Connect via rpcclient to the Samba server and execute the <command>adddriver</command> command with the correct parameters. + </para></listitem> + + <listitem><para> + <indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> + Connect via rpcclient to the Samba server a second time and execute the <command>setdriver</command> command.</para></listitem> +</orderedlist> + +<note> +<para> +You can run the <command>cupsaddsmb</command> utility with parameters to specify one remote host as Samba host +and a second remote host as CUPS host. Especially if you want to get a deeper understanding, it is a good idea +to try it and see more clearly what is going on (though in real life most people will have their CUPS and +Samba servers run on the same host): +<screen> +&rootprompt;<userinput>cupsaddsmb -H sambaserver -h cupsserver -v printer</userinput> +</screen> +</para></note> + +</sect2> + +<sect2> +<title>How to Recognize If cupsaddsmb Completed Successfully</title> + +<para> +You <emphasis>must</emphasis> always check if the utility completed +successfully in all fields. You need at minimum these three messages +among the output: +</para> + +<orderedlist> + <listitem><para><emphasis>Printer Driver infotec_2105 successfully + installed.</emphasis> # (for the W32X86 == Windows NT/200x/XP + architecture).</para></listitem> + + <listitem><para><emphasis>Printer Driver infotec_2105 successfully + installed.</emphasis> # (for the WIN40 == Windows 9x/Me + architecture).</para></listitem> + + <listitem><para><emphasis>Successfully set [printerXPZ] to driver + [printerXYZ].</emphasis></para></listitem> +</orderedlist> + +<para> +These messages are probably not easily recognized in the general +output. If you run <command>cupsaddsmb</command> with the <option>-a</option> +parameter (which tries to prepare <emphasis>all</emphasis> active CUPS +printer drivers for download), you might miss if individual printer +drivers had problems installing properly. A redirection of the +output will help you analyze the results in retrospective. +</para> + +<para> +If you get: +<screen> +SetPrinter call failed! +result was WERR_ACCESS_DENIED +</screen> +it means that you might have set <smbconfoption name="use client driver">yes</smbconfoption> for this printer. +Setting it to <quote>no</quote> will solve the problem. Refer to the &smb.conf; man page for explanation of +the <parameter>use client driver</parameter>. +</para> + +<note><para> +It is impossible to see any diagnostic output if you do not run <command>cupsaddsmb</command> in verbose mode. +Therefore, we strongly recommend against use of the default quiet mode. It will hide any problems from you that +might occur. +</para></note> +</sect2> + +<sect2> +<title>cupsaddsmb with a Samba PDC</title> + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +Can't get the standard <command>cupsaddsmb</command> command to run on a Samba PDC? Are you asked for the +password credential again and again, and the command just will not take off at all? Try one of these +variations: +</para> + +<para><screen> +&rootprompt;<userinput>cupsaddsmb -U &example.workgroup;\\root -v printername</userinput> +&rootprompt;<userinput>cupsaddsmb -H &example.pdc.samba; -U &example.workgroup;\\root -v printername</userinput> +&rootprompt;<userinput>cupsaddsmb -H &example.pdc.samba; -U &example.workgroup;\\root -h cups-server -v printername</userinput> +</screen></para> + +<para> +(Note the two backslashes: the first one is required to <quote>escape</quote> the second one). +</para> +</sect2> + +<sect2> +<title>cupsaddsmb Flowchart</title> + +<para> +<indexterm><primary>cupsaddsmb</primary></indexterm> +<indexterm><primary>raw print</primary></indexterm> +<link linkend="small14">The cupsaddsmb Flowchart</link> shows a chart about the procedures, command flows, and +data flows of the <command>cupaddsmb</command> command. Note again: cupsaddsmb is +not intended to, and does not work with, raw print queues! +</para> + + <figure id="small14"> + <title>cupsaddsmb Flowchart.</title> + <imagefile>14small</imagefile></figure> +</sect2> + +<sect2> +<title>Installing the PostScript Driver on a Client</title> + +<para> +<indexterm><primary>point'n'print</primary></indexterm> +<indexterm><primary>cupsaddsmb</primary></indexterm> +After <command>cupsaddsmb</command> is completed, your driver is prepared for the clients to use. Here are the +steps you must perform to download and install it via Point'n'Print. From a Windows client, browse to the +CUPS/Samba server: +</para> + +<itemizedlist> + + <listitem><para> + <indexterm><primary>"Printers" folder</primary></indexterm> + Open the <guilabel>Printers</guilabel> share of Samba in Network Neighborhood.</para></listitem> + + <listitem><para>Right-click on the printer in question.</para></listitem> + + <listitem><para>From the opening context menu select + <guimenuitem>Install...</guimenuitem> or + <guimenuitem>Connect...</guimenuitem> (depending on the Windows version you use).</para></listitem> +</itemizedlist> + +<para> +After a few seconds, there should be a new printer in your client's <emphasis>local</emphasis> +<guilabel>Printers</guilabel> folder. On Windows XP it will follow a naming convention of +<emphasis>PrinterName on SambaServer</emphasis>. (In my current case it is infotec_2105 on kde-bitshop). If +you want to test it and send your first job from an application like Winword, the new printer appears in a +<filename>\\SambaServer\PrinterName</filename> entry in the drop-down list of available printers. +</para> + +<para> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>Adobe PostScript driver</primary></indexterm> +<indexterm><primary>net use lpt1:</primary></indexterm> +<command>cupsaddsmb</command> will only reliably work with CUPS version 1.1.15 or higher and with Samba +version 2.2.4, or later. If it does not work, or if the automatic printer driver download to the clients does +not succeed, you can still manually install the CUPS printer PPD on top of the Adobe PostScript driver on +clients. Then point the client's printer queue to the Samba printer share for a UNC type of connection: +<screen> +&dosprompt;<userinput>net use lpt1: \\sambaserver\printershare /user:ntadmin</userinput> +</screen> +should you desire to use the CUPS networked PostScript RIP functions. (Note that user <quote>ntadmin</quote> +needs to be a valid Samba user with the required privileges to access the printershare.) This sets up the +printer connection in the traditional LanMan way (not using MS-RPC). +</para> +</sect2> + +<sect2 id="cups-avoidps1"> +<title>Avoiding Critical PostScript Driver Settings on the Client</title> + +<para> +Printing works, but there are still problems. Most jobs print well, some do not print at all. Some jobs have +problems with fonts, which do not look very good. Some jobs print fast and some are dead-slow. Many of these +problems can be greatly reduced or even completely eliminated if you follow a few guidelines. Remember, if +your print device is not PostScript-enabled, you are treating your Ghostscript installation on your CUPS host +with the output your client driver settings produce. Treat it well: +</para> + +<itemizedlist> + <listitem><para> + Avoid the PostScript Output Option: Optimize for Speed setting. Use the Optimize for Portability instead + (Adobe PostScript driver).</para></listitem> + + <listitem><para> + Don't use the Page Independence: NO setting. Instead, use Page Independence: YES (CUPS PostScript Driver). + </para></listitem> + + <listitem><para> + Recommended is the True Type Font Downloading Option: Native True Type over Automatic and Outline; + you should by all means avoid Bitmap (Adobe PostScript Driver).</para></listitem> + + <listitem><para> + Choose True Type Font: Download as Softfont into Printer over the default Replace by Device + Font (for exotic fonts, you may need to change it back to get a printout at all; Adobe).</para></listitem> + + <listitem><para> + Sometimes you can choose PostScript Language Level: in case of problems try 2 + instead of 3 (the latest ESP Ghostscript package handles Level 3 PostScript very well; Adobe). + </para></listitem> + + <listitem><para> + Say Yes to PostScript Error Handler (Adobe).</para></listitem> +</itemizedlist> + +</sect2> +</sect1> + +<sect1> +<title>Installing PostScript Driver Files Manually Using rpcclient</title> + +<para> +Of course, you can run all the commands that are embedded into the +cupsaddsmb convenience utility yourself, one by one, and upload +and prepare the driver files for future client downloads. +</para> + +<orderedlist> + <listitem><para>Prepare Samba (a CUPS print queue with the name of the + printer should be there. We are providing the driver now).</para></listitem> + + <listitem><para>Copy all files to <smbconfsection name="[print$]"/>.</para></listitem> + + <listitem><para> + <indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> + Run <command>rpcclient adddriver</command> + (for each client architecture you want to support).</para></listitem> + + <listitem><para> + <indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> + Run <command>rpcclient setdriver.</command></para></listitem> +</orderedlist> + +<para> +<indexterm><primary>rpcclient</primary><secondary>enumports</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>enumprinters</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>enumdrivers</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> +We are going to do this now. First, read the man page on <parameter>rpcclient</parameter> to get a first idea. +Look at all the printing-related subcommands: <command>enumprinters</command>, <command>enumdrivers</command>, +<command>enumports</command>, <command>adddriver</command>, and <command>setdriver</command> are among the +most interesting ones. <parameter>rpcclient</parameter> implements an important part of the MS-RPC protocol. +You can use it to query (and command) a Windows NT (or 200x/XP) PC, too. MS-RPC is used by Windows clients, +among other things, to benefit from the Point'n'Print features. Samba can now mimic this as well. +</para> + +<sect2> +<title>A Check of the rpcclient man Page</title> + +<para> +First let's check the <parameter>rpcclient</parameter> man page. Here are two relevant passages: +</para> + +<para> +<indexterm><primary>adddriver</primary></indexterm> +<indexterm><primary>AddPrinterDriver()</primary></indexterm> +<indexterm><primary>getdriverdir</primary></indexterm> +<command>adddriver <arch> <config></command> Execute an <command>AddPrinterDriver()</command> RPC +to install the printer driver information on the server. The driver files should already exist in the +directory returned by <command>getdriverdir</command>. Possible values for <parameter>arch</parameter> are the +same as those for the <command>getdriverdir</command> command. The <parameter>config</parameter> parameter is +defined as follows: +<screen> +Long Printer Name:\ +Driver File Name:\ +Data File Name:\ +Config File Name:\ +Help File Name:\ +Language Monitor Name:\ +Default Data Type:\ +Comma Separated list of Files +</screen></para> + +<para> +Any empty fields should be entered as the string <quote>NULL</quote>. +</para> + +<para> +Samba does not need to support the concept of print monitors, since these only apply to local printers whose +drivers can use a bidirectional link for communication. This field should be <quote>NULL</quote>. On a remote +NT print server, the print monitor for a driver must already be installed before adding the driver or else the +RPC will fail. +</para> + +<para> +<indexterm><primary>setdriver</primary></indexterm> +<indexterm><primary>SetPrinter()</primary></indexterm> +<command>setdriver <printername> <drivername></command> Execute a <command>SetPrinter()</command> +command to update the printer driver associated with an installed printer. The printer driver must already be +correctly installed on the print server. +</para> + +<para> +<indexterm><primary>enumprinters</primary></indexterm> +<indexterm><primary>enumdrivers</primary></indexterm> +See also the <command>enumprinters</command> and <command>enumdrivers</command> commands to +obtain a list of installed printers and drivers. +</para> + +</sect2> + +<sect2> +<title>Understanding the rpcclient man Page</title> + +<para> +<indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> +The <emphasis>exact</emphasis> format isn't made too clear by the man page, since you have to deal with some +parameters containing spaces. Here is a better description for it. We have line-broken the command and +indicated the breaks with <quote>\</quote>. Usually you would type the command in one line without the line +breaks: +<screen> +adddriver "Architecture" \ + "LongPrinterName:DriverFile:DataFile:ConfigFile:HelpFile:\ + LanguageMonitorFile:DataType:ListOfFiles,Comma-separated" +</screen></para> + +<para> +What the man pages denote as a simple <parameter><config></parameter> keyword in reality consists of +eight colon-separated fields. The last field may take multiple (in some very insane cases, even 20 different +additional) files. This might sound confusing at first. What the man pages call the +<quote>LongPrinterName</quote> in reality should be called the <quote>Driver Name</quote>. You can name it +anything you want, as long as you use this name later in the <command>rpcclient ... setdriver</command> +command. For practical reasons, many name the driver the same as the printer. +</para> + +<para> +It isn't simple at all. I hear you asking: <quote>How do I know which files are Driver File</quote>, +<quote>Data File</quote>, <quote>Config File</quote>, <quote>Help File</quote> and <quote>Language Monitor +File in each case?</quote> For an answer, you may want to have a look at how a Windows NT box with a shared +printer presents the files to us. Remember that this whole procedure has to be developed by the Samba Team by +listening to the traffic caused by Windows computers on the wire. We may as well turn to a Windows box now and +access it from a UNIX workstation. We will query it with <command>rpcclient</command> to see what it tells us +and try to understand the man page more clearly. +</para> +</sect2> + +<sect2> +<title>Producing an Example by Querying a Windows Box</title> + +<para> +<indexterm><primary>rpcclient</primary><secondary>getdriver</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>getprinter</secondary></indexterm> +We could run <command>rpcclient</command> with a <command>getdriver</command> or a +<command>getprinter</command> subcommand (in level 3 verbosity) against it. Just sit down at a UNIX or Linux +workstation with the Samba utilities installed, then type the following command: +<screen> +&rootprompt;<userinput>rpcclient -U'user%secret' NT-SERVER -c 'getdriver printername 3'</userinput> +</screen></para> + +<para> +From the result it should become clear which is which. Here is an example from my installation: +<indexterm><primary>rpcclient</primary><secondary>getdriver</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -U'Danka%xxxx' W200xSERVER \ + -c'getdriver "DANKA InfoStream Virtual Printer" 3'</userinput> + cmd = getdriver "DANKA InfoStream Virtual Printer" 3 + + [Windows NT x86] + Printer Driver Info 3: + Version: [2] + Driver Name: [DANKA InfoStream] + Architecture: [Windows NT x86] + Driver Path: [C:\WINNT\System32\spool\DRIVERS\W32X86\2\PSCRIPT.DLL] + Datafile: [C:\WINNT\System32\spool\DRIVERS\W32X86\2\INFOSTRM.PPD] + Configfile: [C:\WINNT\System32\spool\DRIVERS\W32X86\2\PSCRPTUI.DLL] + Helpfile: [C:\WINNT\System32\spool\DRIVERS\W32X86\2\PSCRIPT.HLP] + + Dependentfiles: [] + Dependentfiles: [] + Dependentfiles: [] + Dependentfiles: [] + Dependentfiles: [] + Dependentfiles: [] + Dependentfiles: [] + + Monitorname: [] + Defaultdatatype: [] +</screen></para> + +<para> +Some printer drivers list additional files under the label <parameter>Dependentfiles</parameter>, and these +would go into the last field <parameter>ListOfFiles,Comma-separated</parameter>. For the CUPS PostScript +drivers, we do not need any (nor would we for the Adobe PostScript driver); therefore, the field will get a +<quote>NULL</quote> entry. +</para> +</sect2> + +<sect2> +<title>Requirements for adddriver and setdriver to Succeed</title> + +<para> +<indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> +<indexterm><primary>cupsaddsmb</primary></indexterm> +<indexterm><primary>setdriver</primary></indexterm> +From the man page (and from the quoted output of <command>cupsaddsmb</command> above) it becomes clear that +you need to have certain conditions in order to make the manual uploading and initializing of the driver files +succeed. The two <command>rpcclient</command> subcommands (<command>adddriver</command> and +<command>setdriver</command>) need to encounter the following preconditions to complete successfully: +</para> + +<itemizedlist> + <listitem><para>You are connected as <smbconfoption name="printer admin"/> or root (this is + <emphasis>not</emphasis> the <quote>Printer Operators</quote> group in NT, but the <emphasis>printer + admin</emphasis> group as defined in the <smbconfsection name="[global]"/> section of &smb.conf;). + </para></listitem> + + <listitem><para>Copy all required driver files to <filename>\\SAMBA\print$\w32x86</filename> and + <filename>\\SAMBA\print$\win40</filename> as appropriate. They will end up in the <quote>0</quote> respective + <quote>2</quote> subdirectories later. For now, <emphasis>do not</emphasis> put them there; they'll be + automatically used by the <command>adddriver</command> subcommand. (If you use <command>smbclient</command> to + put the driver files into the share, note that you need to escape the <quote>$</quote>: <command>smbclient + //sambaserver/print\$ -U root.</command>)</para></listitem> + + <listitem><para>The user you're connecting as must be able to write to + the <smbconfsection name="[print$]"/> share and create + subdirectories.</para></listitem> + + <listitem><para>The printer you are going to set up for the Windows + clients needs to be installed in CUPS already.</para></listitem> + + <listitem><para> + <indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> + <indexterm><primary>rpcclient</primary><secondary>enumprinters</secondary></indexterm> + The CUPS printer must be known to Samba; otherwise the <command>setdriver</command> subcommand fails with an + NT_STATUS_UNSUCCESSFUL error. To check if the printer is known by Samba, you may use the + <command>enumprinters</command> subcommand to <command>rpcclient</command>. A long-standing bug prevented a + proper update of the printer list until every smbd process had received a SIGHUP or was restarted. Remember + this in case you've created the CUPS printer just recently and encounter problems: try restarting Samba. + </para></listitem> +</itemizedlist> +</sect2> + +<sect2> +<title>Manual Driver Installation in 15 Steps</title> + +<para> +We are going to install a printer driver now by manually executing all +required commands. Because this may seem a rather complicated process at +first, we go through the procedure step by step, explaining every +single action item as it comes up. +</para> + +<procedure> +<title>Manual Driver Installation</title> + + <step> + <title>Install the printer on CUPS.</title> + + <para><screen> + &rootprompt;<userinput>lpadmin -p mysmbtstprn -v socket://10.160.51.131:9100 -E \ + -P canonIR85.ppd</userinput> + </screen></para> + + <para> + This installs a printer with the name <parameter>mysmbtstprn</parameter> + to the CUPS system. The printer is accessed via a socket + (a.k.a. JetDirect or Direct TCP/IP) connection. You need to be root + for this step. + </para> + </step> + + <step> + <title>(Optional.) Check if the printer is recognized by Samba.</title> + + <para> + <indexterm><primary>rpcclient</primary><secondary>enumprinters</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'enumprinters' localhost \ + | grep -C2 mysmbtstprn</userinput> +flags:[0x800000] +name:[\\kde-bitshop\mysmbtstprn] +description:[\\kde-bitshop\mysmbtstprn,,mysmbtstprn] +comment:[mysmbtstprn] +</screen> + </para> + + <para> + This should show the printer in the list. If not, stop and restart the Samba daemon (smbd) or send a HUP signal: +<screen> +&rootprompt;<userinput>kill -HUP `pidof smbd`</userinput> +</screen> + Check again. Troubleshoot and repeat until successful. Note the <quote>empty</quote> field between the two + commas in the <quote>description</quote> line. The driver name would appear here if there was one already. You + need to know root's Samba password (as set by the <command>smbpasswd</command> command) for this step and most + of the following steps. Alternatively, you can authenticate as one of the users from the <quote>write + list</quote> as defined in &smb.conf; for <smbconfsection name="[print$]"/>. + </para> + </step> + + <step> + <title>(Optional.) Check if Samba knows a driver for the printer.</title> + + <para> + <indexterm><primary>rpcclient</primary><secondary>getprinter</secondary></indexterm> + <indexterm><primary>rpcclient</primary><secondary>getdriver</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'getprinter mysmbtstprn 2'\ + localhost | grep driver </userinput> + +drivername:[] + +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'getprinter mysmbtstprn 2' \ + localhost | grep -C4 driv</userinput> + +servername:[\\kde-bitshop] +printername:[\\kde-bitshop\mysmbtstprn] +sharename:[mysmbtstprn] +portname:[Samba Printer Port] +drivername:[] +comment:[mysmbtstprn] +location:[] +sepfile:[] +printprocessor:[winprint] + +&rootprompt;<userinput>rpcclient -U root%xxxx -c 'getdriver mysmbtstprn' localhost</userinput> + result was WERR_UNKNOWN_PRINTER_DRIVER +</screen></para> + +<para> +None of the three commands shown above should show a driver. +This step was done for the purpose of demonstrating this condition. An +attempt to connect to the printer at this stage will prompt a +message along the lines of, <quote>The server does not have the required printer +driver installed.</quote> +</para> +</step> + +<step> +<title>Put all required driver files into Samba's +[print$].</title> + +<para><screen> +&rootprompt;<userinput>smbclient //localhost/print\$ -U 'root%xxxx' \ + -c 'cd W32X86; \ + put /etc/cups/ppd/mysmbtstprn.ppd mysmbtstprn.PPD; \ + put /usr/share/cups/drivers/cupsui.dll cupsui.dll; \ + put /usr/share/cups/drivers/cupsdrvr.dll cupsdrvr.dll; \ + put /usr/share/cups/drivers/cups.hlp cups.hlp'</userinput> +</screen></para> + +<para> +(This command should be entered in one long single line. Line breaks and the line ends indicated by +<quote>\</quote> have been inserted for readability reasons.) This step is <emphasis>required</emphasis> for +the next one to succeed. It makes the driver files physically present in the <smbconfsection name="[print$]"/> +share. However, clients would still not be able to install them, because Samba does not yet treat them as +driver files. A client asking for the driver would still be presented with a <quote>not installed here</quote> +message. +</para> +</step> + +<step> +<title>Verify where the driver files are now.</title> + +<para><screen> +&rootprompt;<userinput>ls -l /etc/samba/drivers/W32X86/</userinput> +total 669 +drwxr-sr-x 2 root ntadmin 532 May 25 23:08 2 +drwxr-sr-x 2 root ntadmin 670 May 16 03:15 3 +-rwxr--r-- 1 root ntadmin 14234 May 25 23:21 cups.hlp +-rwxr--r-- 1 root ntadmin 278380 May 25 23:21 cupsdrvr.dll +-rwxr--r-- 1 root ntadmin 215848 May 25 23:21 cupsui.dll +-rwxr--r-- 1 root ntadmin 169458 May 25 23:21 mysmbtstprn.PPD +</screen></para> + +<para> +The driver files now are in the W32X86 architecture <quote>root</quote> of +<smbconfsection name="[print$]"/>. +</para> +</step> + +<step> +<title>Tell Samba that these are driver files (<command>adddriver</command>).</title> + +<para> +<indexterm><primary>rpcclient</primary><secondary>adddriver</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'adddriver "Windows NT x86" \ + "mydrivername:cupsdrvr.dll:mysmbtstprn.PPD: \ + cupsui.dll:cups.hlp:NULL:RAW:NULL"' \ + localhost</userinput> +Printer Driver mydrivername successfully installed. +</screen></para> + +<para> +You cannot repeat this step if it fails. It could fail even as a result of a simple typo. It will most likely +have moved a part of the driver files into the <quote>2</quote> subdirectory. If this step fails, you need to +go back to the fourth step and repeat it before you can try this one again. In this step, you need to choose a +name for your driver. It is normally a good idea to use the same name as is used for the printer name; +however, in big installations you may use this driver for a number of printers that obviously have different +names, so the name of the driver is not fixed. +</para> +</step> + +<step> +<title>Verify where the driver files are now.</title> + +<para><screen> +&rootprompt;<userinput>ls -l /etc/samba/drivers/W32X86/</userinput> +total 1 +drwxr-sr-x 2 root ntadmin 532 May 25 23:22 2 +drwxr-sr-x 2 root ntadmin 670 May 16 03:15 3 + +&rootprompt;<userinput>ls -l /etc/samba/drivers/W32X86/2</userinput> +total 5039 +[....] +-rwxr--r-- 1 root ntadmin 14234 May 25 23:21 cups.hlp +-rwxr--r-- 1 root ntadmin 278380 May 13 13:53 cupsdrvr.dll +-rwxr--r-- 1 root ntadmin 215848 May 13 13:53 cupsui.dll +-rwxr--r-- 1 root ntadmin 169458 May 25 23:21 mysmbtstprn.PPD +</screen></para> + +<para> +Notice how step 6 also moved the driver files to the appropriate +subdirectory. Compare this with the situation after step 5. +</para> +</step> + +<step> +<title>(Optional.) Verify if Samba now recognizes the driver.</title> + +<para> +<indexterm><primary>rpcclient</primary><secondary>enumdrivers</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'enumdrivers 3' \ + localhost | grep -B2 -A5 mydrivername</userinput> +Printer Driver Info 3: +Version: [2] +Driver Name: [mydrivername] +Architecture: [Windows NT x86] +Driver Path: [\\kde-bitshop\print$\W32X86\2\cupsdrvr.dll] +Datafile: [\\kde-bitshop\print$\W32X86\2\mysmbtstprn.PPD] +Configfile: [\\kde-bitshop\print$\W32X86\2\cupsui.dll] +Helpfile: [\\kde-bitshop\print$\W32X86\2\cups.hlp] +</screen></para> + +<para> +Remember, this command greps for the name you chose for the +driver in step 6. This command must succeed before you can proceed. +</para> +</step> + +<step> +<para><title>Tell Samba which printer should use these driver files (<command>setdriver</command>).</title></para> + +<para> +<indexterm><primary>rpcclient</primary><secondary>setdriver</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'setdriver mysmbtstprn mydrivername' \ + localhost</userinput> +Successfully set mysmbtstprn to driver mydrivername +</screen></para> + +<para> +Since you can bind any printer name (print queue) to any driver, this is a convenient way to set up many +queues that use the same driver. You do not need to repeat all the previous steps for the setdriver command to +succeed. The only preconditions are that <command>enumdrivers</command> must find the driver and +<command>enumprinters</command> must find the printer. +</para> +</step> + +<step> +<title>(Optional) Verify if Samba has recognized this association.</title> + +<para> +<indexterm><primary>rpcclient</primary><secondary>getprinter</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>getdriver</secondary></indexterm> +<indexterm><primary>rpcclient</primary><secondary>enumprinters</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'getprinter mysmbtstprn 2' localhost \ + | grep driver</userinput> +drivername:[mydrivername] + +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'getprinter mysmbtstprn 2' localhost \ + | grep -C4 driv</userinput> +servername:[\\kde-bitshop] +printername:[\\kde-bitshop\mysmbtstprn] +sharename:[mysmbtstprn] +portname:[Done] +drivername:[mydrivername] +comment:[mysmbtstprn] +location:[] +sepfile:[] +printprocessor:[winprint] + +&rootprompt;<userinput>rpcclient -U root%xxxx -c 'getdriver mysmbtstprn' localhost</userinput> +[Windows NT x86] +Printer Driver Info 3: + Version: [2] + Driver Name: [mydrivername] + Architecture: [Windows NT x86] + Driver Path: [\\kde-bitshop\print$\W32X86\2\cupsdrvr.dll] + Datafile: [\\kde-bitshop\print$\W32X86\2\mysmbtstprn.PPD] + Configfile: [\\kde-bitshop\print$\W32X86\2\cupsui.dll] + Helpfile: [\\kde-bitshop\print$\W32X86\2\cups.hlp] + Monitorname: [] + Defaultdatatype: [RAW] + Monitorname: [] + Defaultdatatype: [RAW] + +&rootprompt;<userinput>rpcclient -Uroot%xxxx -c 'enumprinters' localhost \ + | grep mysmbtstprn</userinput> + name:[\\kde-bitshop\mysmbtstprn] + description:[\\kde-bitshop\mysmbtstprn,mydrivername,mysmbtstprn] + comment:[mysmbtstprn] + +</screen></para> + +<para> +<indexterm><primary>rpcclient</primary><secondary>enumprinters</secondary></indexterm> +Compare these results with the ones from steps 2 and 3. Every one of these commands show the driver is installed. Even +the <command>enumprinters</command> command now lists the driver +on the <quote>description</quote> line. +</para> +</step> + +<step> +<title>(Optional.) Tickle the driver into a correct +device mode.</title> + +<para> +<indexterm><primary>"Printers" folder</primary></indexterm> +You certainly know how to install the driver on the client. In case +you are not particularly familiar with Windows, here is a short +recipe: Browse the Network Neighborhood, go to the Samba server, and look +for the shares. You should see all shared Samba printers. +Double-click on the one in question. The driver should get +installed and the network connection set up. Another way is to +open the <guilabel>Printers (and Faxes)</guilabel> folder, right-click on the printer in +question, and select <guilabel>Connect</guilabel> or <guilabel>Install</guilabel>. As a result, a new printer +should appear in your client's local <guilabel>Printers (and Faxes)</guilabel> +folder, named something like <guilabel>printersharename on Sambahostname</guilabel>. +</para> + +<para> +It is important that you execute this step as a Samba printer admin +(as defined in &smb.conf;). Here is another method +to do this on Windows XP. It uses a command line, which you may type +into the <quote>DOS box</quote> (type root's smbpassword when prompted): +</para> + +<para><screen> +&dosprompt;<userinput>runas /netonly /user:root "rundll32 printui.dll,PrintUIEntry \ + /in /n \\sambaserver\mysmbtstprn"</userinput> +</screen></para> + +<para> +Change any printer setting once (like changing <emphasis><guilabel>portrait</guilabel> to +<guilabel>landscape</guilabel></emphasis>), click on <guibutton>Apply</guibutton>, and change the setting back. +</para> +</step> + +<step> +<title>Install the printer on a client (Point'n'Print).</title> + +<para> +<indexterm significance="preferred"><primary>point 'n' print</primary></indexterm> +<screen> +&dosprompt;<userinput>rundll32 printui.dll,PrintUIEntry /in /n "\\sambaserver\mysmbtstprn"</userinput> +</screen> +If it does not work, it could be a permissions problem with the <smbconfsection name="[print$]"/> share. +</para> +</step> + +<step> +<title>(Optional) Print a test page.</title> + +<indexterm><primary>rundll32</primary></indexterm> +<para><screen> +&dosprompt;<userinput>rundll32 printui.dll,PrintUIEntry /p /n "\\sambaserver\mysmbtstprn"</userinput> +</screen></para> + +<para> +Then hit [TAB] five times, [ENTER] twice, [TAB] once, and [ENTER] again, and march to the printer. +</para> +</step> + +<step> +<title>(Recommended.) Study the test page.</title> + +<para> +Hmmm. Just kidding! By now you know everything about printer installations and you do not need to read a word. +Just put it in a frame and bolt it to the wall with the heading "MY FIRST RPCCLIENT-INSTALLED PRINTER" +&smbmdash; why not just throw it away! +</para> +</step> + +<step> +<title>(Obligatory.) Enjoy. Jump. Celebrate your success.</title> + +<para><screen> +&rootprompt;<userinput>echo "Cheeeeerioooooo! Success..." >> /var/log/samba/log.smbd</userinput> +</screen></para> +</step> +</procedure> +</sect2> + +<sect2> +<title>Troubleshooting Revisited</title> + +<para> +<indexterm><primary>adddriver</primary></indexterm> +The setdriver command will fail if in Samba's mind the queue is not +already there. A successful installation displys the promising message that the: +<screen> +Printer Driver ABC successfully installed. +</screen> +following the <command>adddriver</command> parts of the procedure. But you may also see +a disappointing message like this one: +<computeroutput> +result was NT_STATUS_UNSUCCESSFUL +</computeroutput></para> + +<para> +<indexterm><primary>lpstat</primary></indexterm> +<indexterm><primary>rpcclient</primary></indexterm> +It is not good enough that you can see the queue in CUPS, using the <command>lpstat -p ir85wm</command> +command. A bug in most recent versions of Samba prevents the proper update of the queue list. The recognition +of newly installed CUPS printers fails unless you restart Samba or send a HUP to all smbd processes. To verify +if this is the reason why Samba does not execute the <command>setdriver</command> command successfully, check +if Samba <quote>sees</quote> the printer: +<indexterm><primary>rpcclient</primary><secondary>enumprinters</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient transmeta -N -U'root%xxxx' -c 'enumprinters 0'|grep ir85wm</userinput> + printername:[ir85wm] +</screen></para> + +<para> +An alternate command could be this: +<indexterm><primary>rpcclient</primary><secondary>getprinter</secondary></indexterm> +<screen> +&rootprompt;<userinput>rpcclient transmeta -N -U'root%secret' -c 'getprinter ir85wm' </userinput> + cmd = getprinter ir85wm + flags:[0x800000] + name:[\\transmeta\ir85wm] + description:[\\transmeta\ir85wm,ir85wm,DPD] + comment:[CUPS PostScript-Treiber for Windows NT/200x/XP] +</screen></para> + +<para> +By the way, you can use these commands, plus a few more, of course, to install drivers on remote Windows NT print servers too! +</para> +</sect2> +</sect1> + +<sect1> +<title>The Printing <filename>*.tdb</filename> Files</title> + +<para> +<indexterm><primary>TDB</primary></indexterm> +<indexterm><primary>connections.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>printing.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>share_info.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>ntdrivers.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>unexpected.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>brlock.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>locking.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>ntforms.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>messages.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>ntprinters.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>sessionid.tdb</primary><seealso>TDB</seealso></indexterm> +<indexterm><primary>secrets.tdb</primary><seealso>TDB</seealso></indexterm> +Some mystery is associated with the series of files with a tdb suffix appearing in every Samba installation. +They are <filename>connections.tdb</filename>, <filename>printing.tdb</filename>, +<filename>share_info.tdb</filename>, <filename>ntdrivers.tdb</filename>, <filename>unexpected.tdb</filename>, +<filename>brlock.tdb</filename>, <filename>locking.tdb</filename>, <filename>ntforms.tdb</filename>, +<filename>messages.tdb</filename> , <filename>ntprinters.tdb</filename>, <filename>sessionid.tdb</filename>, +and <filename>secrets.tdb</filename>. What is their purpose? +</para> + +<sect2> +<title>Trivial Database Files</title> + +<para> +<indexterm><primary>TDB</primary></indexterm> +A Windows NT (print) server keeps track of all information needed to serve its duty toward its clients by +storing entries in the Windows registry. Client queries are answered by reading from the registry, +Administrator or user configuration settings that are saved by writing into the registry. Samba and UNIX +obviously do not have such a Registry. Samba instead keeps track of all client-related information in a series +of <filename>*.tdb</filename> files. (TDB stands for trivial data base). These are often located in +<filename>/var/lib/samba/</filename> or <filename>/var/lock/samba/</filename>. The printing-related files are +<filename>ntprinters.tdb</filename>, <filename>printing.tdb</filename>,<filename>ntforms.tdb</filename>, and +<filename>ntdrivers.tdb</filename>. +</para> +</sect2> + +<sect2> +<title>Binary Format</title> + +<para> +<filename>*.tdb</filename> files are not human readable. They are written in a binary format. <quote>Why not +ASCII?</quote>, you may ask. <quote>After all, ASCII configuration files are a good and proven tradition on +UNIX.</quote> The reason for this design decision by the Samba Team is mainly performance. Samba needs to be +fast; it runs a separate <command>smbd</command> process for each client connection, in some environments many +thousands of them. Some of these <command>smbds</command> might need to write-access the same +<filename>*.tdb</filename> file <emphasis>at the same time</emphasis>. The file format of Samba's +<filename>*.tdb</filename> files allows for this provision. Many smbd processes may write to the same +<filename>*.tdb</filename> file at the same time. This wouldn't be possible with pure ASCII files. +</para> +</sect2> + +<sect2> +<title>Losing <filename>*.tdb</filename> Files</title> + +<para> +It is very important that all <filename>*.tdb</filename> files remain consistent over all write and read +accesses. However, it may happen that these files <emphasis>do</emphasis> get corrupted. (A <command>kill -9 +`pidof smbd'</command> while a write access is in progress could do the damage, as could a power interruption, +etc.). In cases of trouble, a deletion of the old printing-related <filename>*.tdb</filename> files may be the +only option. After that, you need to re-create all print-related setups unless you have made a backup of the +<filename>*.tdb</filename> files in time. +</para> +</sect2> + +<sect2> +<title>Using <command>tdbbackup</command></title> + +<para> +<indexterm><primary>TDB</primary><secondary>backing up</secondary><see>tdbbackup</see></indexterm> +<indexterm><primary>tdbbackup</primary></indexterm> +Samba ships with a little utility that helps the root user of your system to backup your +<filename>*.tdb</filename> files. If you run it with no argument, it prints a usage message: +<screen> +&rootprompt;<userinput>tdbbackup</userinput> + Usage: tdbbackup [options] <fname...> + + Version:3.0a + -h this help message + -s suffix set the backup suffix + -v verify mode (restore if corrupt) +</screen></para> + +<para> +Here is how I backed up my <filename>printing.tdb</filename> file: +</para> + +<para><screen> +&rootprompt;<userinput>ls</userinput> +. browse.dat locking.tdb ntdrivers.tdb printing.tdb +.. share_info.tdb connections.tdb messages.tdb ntforms.tdb +printing.tdbkp unexpected.tdb brlock.tdb gmon.out namelist.debug +ntprinters.tdb sessionid.tdb + +&rootprompt;<userinput>tdbbackup -s .bak printing.tdb</userinput> + printing.tdb : 135 records + +&rootprompt;<userinput>ls -l printing.tdb*</userinput> + -rw------- 1 root root 40960 May 2 03:44 printing.tdb + -rw------- 1 root root 40960 May 2 03:44 printing.tdb.bak + +</screen></para> +</sect2> +</sect1> + +<sect1> +<title>CUPS Print Drivers from Linuxprinting.org</title> + +<para> +<indexterm><primary>Linuxprinting.org</primary></indexterm> +CUPS ships with good support for HP LaserJet-type printers. You can install the generic driver as follows: +<indexterm><primary>lpadmin</primary></indexterm> +<screen> +&rootprompt;<userinput>lpadmin -p laserjet4plus -v parallel:/dev/lp0 -E -m laserjet.ppd</userinput> +</screen></para> + +<para> +The <option>-m</option> switch will retrieve the <filename>laserjet.ppd</filename> from the standard +repository for not-yet-installed PPDs, which CUPS typically stores in +<filename>/usr/share/cups/model</filename>. Alternatively, you may use <option>-P /path/to/your.ppd</option>. +</para> + +<para> +The generic <filename>laserjet.ppd,</filename> however, does not support every special option for every +LaserJet-compatible model. It constitutes a sort of <quote>least common denominator</quote> of all the models. +If for some reason you must pay for the commercially available ESP Print Pro drivers, your first move should +be to consult the database on the <ulink noescape="1" +url="http://www.linuxprinting.org/printer_list.cgi">Linuxprinting</ulink> Web site. Linuxprinting.org has +excellent recommendations about which driver is best used for each printer. Its database is kept current by +the tireless work of Till Kamppeter from Mandrakesoft, who is also the principal author of the +<command>foomatic-rip</command> utility. +</para> + +<note><para> +<indexterm><primary>foomatic-rip</primary></indexterm> +<indexterm><primary>cupsomatic</primary></indexterm> +<indexterm><primary>Adobe PPD</primary></indexterm> +The former <command>cupsomatic</command> concept is now being replaced by the new successor, a much more +powerful <command>foomatic-rip</command>. <command>cupsomatic</command> is no longer maintained. Here is the +new URL to the <ulink noescape="1" url="http://www.linuxprinting.org/driver_list.cgi">Foomatic-3.0</ulink> +database. If you upgrade to <command>foomatic-rip</command>, remember to also upgrade to the new-style PPDs +for your Foomatic-driven printers. foomatic-rip will not work with PPDs generated for the old +<command>cupsomatic</command>. The new-style PPDs are 100% compliant with the Adobe PPD specification. They +are also intended to be used by Samba and the cupsaddsmb utility, to provide the driver files for the Windows +clients! +</para></note> + +<sect2> +<title>foomatic-rip and Foomatic Explained</title> + + +<para> +<indexterm significance="preferred"><primary>foomatic</primary></indexterm> +<indexterm significance="preferred"><primary>foomatic-rip</primary></indexterm> +Nowadays, most Linux distributions rely on the utilities from the <ulink +url="http://www.linuxprinting.org/">Linuxprinting.org</ulink> to create their printing-related software +(which, by the way, works on all UNIXes and on Mac OS X and Darwin, too). The utilities from this sire have a +very end-user-friendly interface that allows for an easy update of drivers and PPDs for all supported models, +all spoolers, all operating systems, and all package formats (because there is none). Its history goes back a +few years. +</para> + +<para> +Recently, Foomatic has achieved the astonishing milestone of <ulink +url="http://www.linuxprinting.org/printer_list.cgi?make=Anyone">1,000 listed</ulink> printer models. +Linuxprinting.org keeps all the important facts about printer drivers, supported models, and which options are +available for the various driver/printer combinations in its <ulink +url="http://www.linuxprinting.org/foomatic.html">Foomatic</ulink> database. Currently there are <ulink +url="http://www.linuxprinting.org/driver_list.cgi">245 drivers</ulink> in the database. Many drivers support +various models, and many models may be driven by different drivers &smbmdash; its your choice! +</para> + +<sect3> +<title>690 <quote>Perfect</quote> Printers</title> + +<para> +<indexterm><primary>Windows PPD</primary></indexterm> +At present, there are 690 devices dubbed as working perfectly: 181 are <emphasis>mostly</emphasis> perfect, 96 +are <emphasis>partially</emphasis> perfect, and 46 are paperweights. Keeping in mind that most of these are +non-PostScript models (PostScript printers are automatically supported by CUPS to perfection by using their +own manufacturer-provided Windows PPD), and that a multifunctional device never qualifies as working perfectly +if it does not also scan and copy and fax under GNU/Linux &smbmdash; then this is a truly astonishing +achievement! Three years ago the number was not more than 500, and Linux or UNIX printing at the time wasn't +anywhere near the quality it is today. +</para> +</sect3> + +<sect3> +<title>How the Printing HOWTO Started It All</title> + +<para> +A few years ago <ulink url="http://www2.picante.com/">Grant Taylor</ulink> started it all. The +roots of today's Linuxprinting.org are in the first <ulink +url="http://www.linuxprinting.org/foomatic2.9/howto/">Linux Printing HOWTO</ulink> that he authored. As a +side-project to this document, which served many Linux users and admins to guide their first steps in this +complicated and delicate setup (to a scientist, printing is <quote>applying a structured deposition of +distinct patterns of ink or toner particles on paper substrates</quote>), he started to build in a little +Postgres database with information about the hardware and driver zoo that made up Linux printing of the time. +This database became the core component of today's Foomatic collection of tools and data. In the meantime, it +has moved to an XML representation of the data. +</para> +</sect3> + +<sect3> +<title>Foomatic's Strange Name</title> + + +<para> +<indexterm><primary>foomatic</primary></indexterm> +<quote>Why the funny name?</quote> you ask. When it really took off, around spring 2000, CUPS was far less +popular than today, and most systems used LPD, LPRng, or even PDQ to print. CUPS shipped with a few generic +drivers (good for a few hundred different printer models). These didn't support many device-specific options. +CUPS also shipped with its own built-in rasterization filter (<parameter>pstoraster</parameter>, derived from +Ghostscript). On the other hand, CUPS provided brilliant support for <emphasis>controlling</emphasis> all +printer options through standardized and well-defined PPD files. Plus, CUPS was designed to be easily +extensible. +</para> + +<para> +Taylor already had in his database a respectable compilation of facts about many more printers and the +Ghostscript <quote>drivers</quote> they run with. His idea, to generate PPDs from the database information and +use them to make standard Ghostscript filters work within CUPS, proved to work very well. It also killed +several birds with one stone: +</para> + +<itemizedlist> + <listitem><para>It made all current and future Ghostscript filter + developments available for CUPS.</para></listitem> + + <listitem><para>It made available a lot of additional printer models + to CUPS users (because often the traditional Ghostscript way of + printing was the only one available).</para></listitem> + + <listitem><para>It gave all the advanced CUPS options (Web interface, + GUI driver configurations) to users wanting (or needing) to use + Ghostscript filters.</para></listitem> +</itemizedlist> +</sect3> + +<sect3> +<title>cupsomatic, pdqomatic, lpdomatic, directomatic</title> + +<para> +<indexterm><primary>cupsomatic</primary></indexterm> +<indexterm><primary>CUPS-PPD</primary></indexterm> +<indexterm><primary>PPD</primary><secondary>CUPS</secondary><see>CUPS-PPD</see></indexterm> +CUPS worked through a quickly hacked-up filter script named <ulink +url="http://www.linuxprinting.org/download.cgi?filename=cupsomatic&show=0">cupsomatic</ulink>. cupsomatic +ran the printfile through Ghostscript, constructing automatically the rather complicated command line needed. +It just needed to be copied into the CUPS system to make it work. To configure the way cupsomatic controls the +Ghostscript rendering process, it needs a CUPS-PPD. This PPD is generated directly from the contents of the +database. For CUPS and the respective printer/filter combo, another Perl script named CUPS-O-Matic did the PPD +generation. After that was working, Taylor implemented within a few days a similar thing for two other +spoolers. Names chosen for the config-generator scripts were <ulink +url="http://www.linuxprinting.org/download.cgi?filename=lpdomatic&show=0">PDQ-O-Matic</ulink> (for PDQ) +and <ulink url="http://www.linuxprinting.org/download.cgi?filename=lpdomatic&show=0">LPD-O-Matic</ulink> +(for &smbmdash; you guessed it &smbmdash; LPD); the configuration here didn't use PPDs but other +spooler-specific files. +</para> + +<para> +From late summer of that year, <ulink url="http://www.linuxprinting.org/till/">Till Kamppeter</ulink> started +to put work into the database. Kamppeter had been newly employed by <ulink +url="http://www.mandrakesoft.com/">Mandrakesoft</ulink> to convert its printing system over to CUPS, after +they had seen his <ulink url="http://www.fltk.org/">FLTK</ulink>-based <ulink +url="http://cups.sourceforge.net/xpp/">XPP</ulink> (a GUI front-end to the CUPS lp-command). He added a huge +amount of new information and new printers. He also developed the support for other spoolers, like <ulink +url="http://ppr.sourceforge.net/">PPR</ulink> (via ppromatic), <ulink +url="http://sourceforge.net/projects/lpr/">GNUlpr</ulink>, and <ulink +url="http://www.lprng.org/">LPRng</ulink> (both via an extended lpdomatic) and spooler-less printing (<ulink +url="http://www.linuxprinting.org/download.cgi?filename=directomatic&show=0">directomatic</ulink>). +</para> + +<para> +So, to answer your question, <quote>Foomatic</quote> is the general name for all the overlapping code and data +behind the <quote>*omatic</quote> scripts. Foomatic, up to versions 2.0.x, required (ugly) Perl data +structures attached to Linuxprinting.org PPDs for CUPS. It had a different <quote>*omatic</quote> script for +every spooler, as well as different printer configuration files. +</para> +</sect3> + +<sect3> +<title>The <emphasis>Grand Unification</emphasis> Achieved</title> + +<para> +<indexterm><primary>foomatic-rip</primary></indexterm> +This has all changed in Foomatic versions 2.9 (beta) and released as <quote>stable</quote> 3.0. It has now +achieved the convergence of all *omatic scripts and is called the <ulink +url="http://www.linuxprinting.org/foomatic2.9/download.cgi?filename=foomatic-rip&show=0">foomatic-rip</ulink>. +This single script is the unification of the previously different spooler-specific *omatic scripts. +foomatic-rip is used by all the different spoolers alike, and because it can read PPDs (both the original +PostScript printer PPDs and the Linuxprinting.org-generated ones), all of a sudden all supported spoolers can +have the power of PPDs at their disposal. Users only need to plug foomatic-rip into their system. For users +there is improved media type and source support &smbmdash; paper sizes and trays are easier to configure. +</para> + +<para> +<indexterm><primary>PPDs</primary></indexterm> +<indexterm><primary>Foomatic tutorial</primary></indexterm> +<indexterm><primary>LinuxKongress2002</primary></indexterm> +Also, the new generation of Linuxprinting.org PPDs no longer contains Perl data structures. If you are a +distro maintainer and have used the previous version of Foomatic, you may want to give the new one a spin, but +remember to generate a new-version set of PPDs via the new <ulink +url="http://www.linuxprinting.org/download/foomatic/foomatic-db-engine-3.0.0beta1.tar.gz">foomatic-db-engine!</ulink>. +Individual users just need to generate a single new PPD specific to their model by <ulink +url="http://www.linuxprinting.org/kpfeifle/LinuxKongress2002/Tutorial/II.Foomatic-User/II.tutorial-handout-foomatic-user.html">following +the steps</ulink> outlined in the Foomatic tutorial or in this chapter. This new development is truly amazing. +</para> + +<para> +<indexterm><primary>foomatic-rip</primary></indexterm> +<indexterm><primary>Adobe</primary></indexterm> +<indexterm><primary>printer drivers</primary></indexterm> +foomatic-rip is a very clever wrapper around the need to run Ghostscript with a different syntax, options, +device selections, and/or filters for each different printer or spooler. At the same time, it can read the PPD +associated with a print queue and modify the print job according to the user selections. Together with this +comes the 100% compliance of the new Foomatic PPDs with the Adobe spec. Some innovative features of the +Foomatic concept may surprise users. It will support custom paper sizes for many printers and will support +printing on media drawn from different paper trays within the same job (in both cases, even where there is no +support for this from Windows-based vendor printer drivers). +</para> +</sect3> + +<sect3> +<title>Driver Development Outside</title> + +<para> +<indexterm><primary>Linuxprinting.org</primary></indexterm> +Most driver development itself does not happen within Linuxprinting.org. Drivers are written by independent +maintainers. Linuxprinting.org just pools all the information and stores it in its database. In addition, it +also provides the Foomatic glue to integrate the many drivers into any modern (or legacy) printing system +known to the world. +</para> + +<para> +Speaking of the different driver development groups, most of the work is currently done in three projects: +</para> + +<itemizedlist> + <listitem><para> +<indexterm><primary>Omni</primary></indexterm> + <ulink url="http://www-124.ibm.com/developerworks/oss/linux/projects/omni/">Omni</ulink> + &smbmdash; a free software project by IBM that tries to convert its printer + driver knowledge from good-ol' OS/2 times into a modern, modular, + universal driver architecture for Linux/UNIX (still beta). This + currently supports 437 models.</para></listitem> + + <listitem><para> +<indexterm><primary>HPIJS</primary></indexterm> + <ulink url="http://hpinkjet.sf.net/">HPIJS</ulink> &smbmdash; + a free software project by HP to provide the support for its own + range of models (very mature, printing in most cases is perfect and + provides true photo quality). This currently supports 369 + models.</para></listitem> + + <listitem><para> +<indexterm><primary>Gimp-Print</primary></indexterm> + <ulink url="http://gimp-print.sf.net/">Gimp-Print</ulink> &smbmdash; a free software + effort, started by Michael Sweet (also lead developer for CUPS), now + directed by Robert Krawitz, which has achieved an amazing level of + photo print quality (many Epson users swear that its quality is + better than the vendor drivers provided by Epson for the Microsoft + platforms). This currently supports 522 models.</para></listitem> +</itemizedlist> +</sect3> + +<sect3> +<title>Forums, Downloads, Tutorials, Howtos (Also for Mac OS X and Commercial UNIX)</title> + +<para> +Linuxprinting.org today is the one-stop shop to download printer drivers. Look for printer information and +<ulink url="http://www.linuxprinting.org//kpfeifle/LinuxKongress2002/Tutorial/">tutorials</ulink> or solve +printing problems in its popular <ulink url="http://www.linuxprinting.org/newsportal/">forums</ulink>. This +forum is not just for GNU/Linux users, but admins of <ulink url="http://www.linuxprinting.org/macosx/"> +commercial UNIX systems</ulink> are also going there, and the relatively new +<ulink url="http://www.linuxprinting.org/newsportal/thread.php3?name=linuxprinting.macosx.general">Mac OS X +forum</ulink> has turned out to be one of the most frequented forums after only a few weeks. +</para> + +<para> +<indexterm><primary>Mandriva</primary></indexterm> +<indexterm><primary>Mandrake</primary></indexterm> +<indexterm><primary>Conectiva</primary></indexterm> +Linuxprinting.org and the Foomatic driver wrappers around Ghostscript are now a standard tool-chain for +printing on all the important distros. Most of them also have CUPS underneath. While in recent years most +printer data had been added by Kamppeter, many additional contributions came from engineers with SuSE, Red +Hat, Conectiva, Debian, and others. Vendor-neutrality is an important goal of the Foomatic project. Mandrake +and Conectiva have merged and are now called Mandriva. +</para> + +<note><para> +Till Kamppeter from Mandrakesoft is doing an excellent job in his spare time to maintain Linuxprinting.org and +Foomatic. So if you use it often, please send him a note showing your appreciation. +</para></note> +</sect3> + +<sect3> +<title>Foomatic Database-Generated PPDs</title> + +<para> +<indexterm><primary>Foomatic database</primary></indexterm> +<indexterm><primary>XML-based datasets</primary></indexterm> +<indexterm><primary>kprinter</primary></indexterm> +<indexterm><primary>gtklp</primary></indexterm> +<indexterm><primary>xpp</primary></indexterm> +<indexterm><primary>HP Photosmart</primary></indexterm> +<indexterm><primary>Epson Stylus inkjet</primary></indexterm> +<indexterm><primary>non-PostScript printers</primary></indexterm> +<indexterm><primary>raster</primary></indexterm> +The Foomatic database is an amazing piece of ingenuity in itself. Not only does it keep the printer and driver +information, but it is organized in a way that it can generate PPD files on the fly from its internal +XML-based datasets. While these PPDs are modeled to the Adobe specification of PPDs, the +Linuxprinting.org/Foomatic-PPDs do not normally drive PostScript printers. They are used to describe all the +bells and whistles you could ring or blow on an Epson Stylus inkjet, or an HP Photosmart, or what-have-you. +The main trick is one little additional line, not envisaged by the PPD specification, starting with the +<parameter>*cupsFilter</parameter> keyword. It tells the CUPS daemon how to proceed with the PostScript print +file (old-style Foomatic-PPDs named the cupsomatic filter script, while the new-style PPDs are now call +foomatic-rip). This filter script calls Ghostscript on the host system (the recommended variant is ESP +Ghostscript) to do the rendering work. foomatic-rip knows which filter or internal device setting it should +ask from Ghostscript to convert the PostScript print job into a raster format ready for the target device. +This usage of PPDs to describe the options of non-PostScript printers was the invention of the CUPS +developers. The rest is easy. GUI tools (like KDE's marvelous <ulink +url="http://printing.kde.org/overview/kprinter.phtml">kprinter</ulink> or the GNOME <ulink +url="http://gtklp.sourceforge.net/">gtklp</ulink> xpp and the CUPS Web interface) read the PPD as well and use +this information to present the available settings to the user as an intuitive menu selection. +</para> +</sect3> +</sect2> + +<sect2> +<title>foomatic-rip and Foomatic PPD Download and Installation</title> + +<para> +Here are the steps to install a foomatic-rip-driven LaserJet 4 Plus-compatible +printer in CUPS (note that recent distributions of SuSE, UnitedLinux and +Mandrake may ship with a complete package of Foomatic-PPDs plus the +<command>foomatic-rip</command> utility. Going directly to +Linuxprinting.org ensures that you get the latest driver/PPD files). +</para> + +<itemizedlist> + <listitem><para>Open your browser at the Linuxprinting.org printer list <ulink url="http://www.linuxprinting.org/printer_list.cgi">page.</ulink> + </para></listitem> + + <listitem><para>Check the complete list of printers in the + <ulink url="http://www.linuxprinting.org/printer_list.cgi?make=Anyone">database.</ulink>. + </para></listitem> + + <listitem><para>Select your model and click on the link. + </para></listitem> + + <listitem><para>You'll arrive at a page listing all drivers working with this + model (for all printers, there will always be <emphasis>one</emphasis> + recommended driver. Try this one first). + </para></listitem> + + <listitem><para>In our case (HP LaserJet 4 Plus), we'll arrive at the default driver for the + <ulink url="http://www.linuxprinting.org/show_printer.cgi?recnum=HP-LaserJet_4_Plus">HP-LaserJet 4 Plus.</ulink> + </para></listitem> + + <listitem><para>The recommended driver is ljet4.</para></listitem> + + <listitem><para>Several links are provided here. You should visit them all if you + are not familiar with the Linuxprinting.org database. + </para></listitem> + + <listitem><para>There is a link to the database page for the + <ulink url="http://www.linuxprinting.org/show_driver.cgi?driver=ljet4">ljet4</ulink>. + On the driver's page, you'll find important and detailed information + about how to use that driver within the various available + spoolers.</para></listitem> + + <listitem><para>Another link may lead you to the home page of the + author of the driver.</para></listitem> + + <listitem><para>Important links are the ones that provide hints with + setup instructions for <ulink noescape="1" url="http://www.linuxprinting.org/cups-doc.html">CUPS</ulink>; + <ulink url="http://www.linuxprinting.org/pdq-doc.html">PDQ</ulink>; + <ulink url="http://www.linuxprinting.org/lpd-doc.html">LPD, LPRng, and GNUlpr</ulink>); + as well as <ulink url="http://www.linuxprinting.org/ppr-doc.html">PPR</ulink> + or <quote>spoolerless</quote> <ulink url="http://www.linuxprinting.org/direct-doc.html">printing</ulink>. + </para></listitem> + + <listitem><para>You can view the PPD in your browser through this link: + <ulink noescape="1" url="http://www.linuxprinting.org/ppd-o-matic.cgi?driver=ljet4&printer=HP-LaserJet_4_Plus&show=1">http://www.linuxprinting.org/ppd-o-matic.cgi?driver=ljet4&printer=HP-LaserJet_4_Plus&show=1</ulink> + </para></listitem> <listitem><para>Most importantly, you can also generate and download + the <ulink url="http://www.linuxprinting.org/ppd-o-matic.cgi?driver=ljet4&printer=HP-LaserJet_4_Plus&show=0">PPD</ulink>. + </para></listitem> + + <listitem><para>The PPD contains all the information needed to use our + model and the driver; once installed, this works transparently + for the user. Later you'll only need to choose resolution, paper size, + and so on, from the Web-based menu, or from the print dialog GUI, or from + the command line.</para></listitem> + + <listitem><para>If you ended up on the drivers + <ulink url="http://www.linuxprinting.org/show_driver.cgi?driver=ljet4">page</ulink>, + you can choose to use the <quote>PPD-O-Matic</quote> online PPD generator + program.</para></listitem> + + <listitem><para>Select the exact model and check either <guilabel>Download</guilabel> or + <guilabel>Display PPD file</guilabel> and click <guilabel>Generate PPD file</guilabel>.</para></listitem> + + <listitem><para>If you save the PPD file from the browser view, please + do not use cut and paste (since it could possibly damage line endings + and tabs, which makes the PPD likely to fail its duty), but use <guimenuitem>Save + as...</guimenuitem> in your browser's menu. (It is best to use the <guilabel>Download</guilabel> option + directly from the Web page.)</para></listitem> + + <listitem><para>Another interesting part on each driver page is + the <guimenuitem>Show execution details</guimenuitem> button. If you + select your printer model and click on that button, + a complete Ghostscript command line will be displayed, enumerating all options + available for that combination of driver and printer model. This is a great way to + <quote>learn Ghostscript by doing</quote>. It is also an excellent cheat sheet + for all experienced users who need to reconstruct a good command line + for that darned printing script, but can't remember the exact + syntax. </para></listitem> + + <listitem><para>Sometime during your visit to Linuxprinting.org, save + the PPD to a suitable place on your hard disk, say + <filename>/path/to/my-printer.ppd</filename> (if you prefer to install + your printers with the help of the CUPS Web interface, save the PPD to + the <filename>/usr/share/cups/model/</filename> path and restart + cupsd).</para></listitem> + + <listitem><para>Then install the printer with a suitable command line, + like this: + </para> + + <para><screen> + &rootprompt;<userinput>lpadmin -p laserjet4plus -v parallel:/dev/lp0 -E \ + -P path/to/my-printer.ppd</userinput> + </screen></para></listitem> + + <listitem><para>For all the new-style <quote>Foomatic-PPDs</quote> + from Linuxprinting.org, you also need a special CUPS filter named + foomatic-rip. + </para></listitem> + + <listitem><para>The foomatic-rip Perl script itself also makes some + interesting <ulink url="http://www.linuxprinting.org/foomatic2.9/download.cgi?filename=foomatic-rip&show=1">reading</ulink> + because it is well documented by Kamppeter's in-line comments (even + non-Perl hackers will learn quite a bit about printing by reading + it).</para></listitem> + + <listitem><para>Save foomatic-rip either directly in + <filename>/usr/lib/cups/filter/foomatic-rip</filename> or somewhere in + your $PATH (and remember to make it world-executable). Again, + do not save by copy and paste but use the appropriate link or the + <guimenuitem>Save as...</guimenuitem> menu item in your browser.</para></listitem> + + <listitem><para>If you save foomatic-rip in your $PATH, create a symlink: + <screen> + &rootprompt;<userinput>cd /usr/lib/cups/filter/ ; ln -s `which foomatic-rip'</userinput> + </screen> + </para> + + <para> + CUPS will discover this new available filter at startup after restarting + cupsd.</para></listitem> +</itemizedlist> + +<para> +Once you print to a print queue set up with the Foomatic PPD, CUPS will insert the appropriate commands and +comments into the resulting PostScript job file. foomatic-rip is able to read and act upon these and uses some +specially encoded Foomatic comments embedded in the job file. These in turn are used to construct +(transparently for you, the user) the complicated Ghostscript command line telling the printer driver exactly +how the resulting raster data should look and which printer commands to embed into the data stream. You need: +</para> + +<itemizedlist> + <listitem><para>A <quote>foomatic+something</quote> PPD &smbmdash; but this is not enough + to print with CUPS (it is only <emphasis>one</emphasis> important + component).</para></listitem> + + <listitem><para>The <parameter>foomatic-rip</parameter> filter script (Perl) in + <filename>/usr/lib/cups/filters/</filename>.</para></listitem> + + <listitem><para>Perl to make foomatic-rip run.</para></listitem> + + <listitem><para>Ghostscript (because it is doing the main work, + controlled by the PPD/foomatic-rip combo) to produce the raster data + fit for your printer model's consumption.</para></listitem> + + <listitem><para>Ghostscript <emphasis>must</emphasis> (depending on + the driver/model) contain support for a certain device representing + the selected driver for your model (as shown by <command>gs -h</command>).</para></listitem> + + <listitem><para>foomatic-rip needs a new version of PPDs (PPD versions + produced for cupsomatic do not work with foomatic-rip).</para></listitem> +</itemizedlist> +</sect2> +</sect1> + +<sect1> +<title>Page Accounting with CUPS</title> + + +<para> +<indexterm><primary>CUPS</primary><secondary>Page Accounting</secondary></indexterm> +Often there are questions regarding print quotas where Samba users (that is, Windows clients) should not be +able to print beyond a certain number of pages or data volume per day, week, or month. This feature is +dependent on the real print subsystem you're using. Samba's part is always to receive the job files from the +clients (filtered <emphasis>or</emphasis> unfiltered) and hand them over to this printing subsystem. +</para> + +<para> +Of course one could hack things with one's own scripts. But then there is CUPS. CUPS supports quotas that can +be based on the size of jobs or on the number of pages or both, and can span any time period you want. +</para> + +<sect2> +<title>Setting Up Quotas</title> + +<para> +<indexterm><primary>CUPS</primary><secondary>quotas</secondary></indexterm> +This is an example command of how root would set a print quota in CUPS, assuming an existing printer named +<quote>quotaprinter</quote>: +<indexterm><primary>lpadmin</primary></indexterm> +<screen> +&rootprompt;<userinput>lpadmin -p quotaprinter -o job-quota-period=604800 \ + -o job-k-limit=1024 -o job-page-limit=100</userinput> +</screen></para> + +<para> +This would limit every single user to print no more than 100 pages or 1024 KB of +data (whichever comes first) within the last 604,800 seconds ( = 1 week). +</para> +</sect2> + +<sect2> +<title>Correct and Incorrect Accounting</title> + +<para> +For CUPS to count correctly, the printfile needs to pass the CUPS pstops filter; otherwise it uses a dummy +count of <quote>one</quote>. Some print files do not pass it (e.g., image files), but then those are mostly +one-page jobs anyway. This also means that proprietary drivers for the target printer running on the client +computers and CUPS/Samba, which then spool these files as <quote>raw</quote> (i.e., leaving them untouched, +not filtering them), will be counted as one-pagers too! +</para> + +<para> +You need to send PostScript from the clients (i.e., run a PostScript driver there) to have the chance to get +accounting done. If the printer is a non-PostScript model, you need to let CUPS do the job to convert the file +to a print-ready format for the target printer. This is currently working for about a thousand different +printer models. Linuxprinting.org has a driver <ulink url="http://www.linuxprinting.org/printer_list.cgi">list</ulink>. +</para> +</sect2> + +<sect2> +<title>Adobe and CUPS PostScript Drivers for Windows Clients</title> + +<para> +<indexterm><primary>Adobe PostScript</primary></indexterm> +<indexterm><primary>pstops</primary></indexterm> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>pstoraster</primary></indexterm> +<indexterm><primary>PJL-header</primary></indexterm> +Before CUPS 1.1.16, your only option was to use the Adobe PostScript driver on the Windows clients. The output +of this driver was not always passed through the <command>pstops</command> filter on the CUPS/Samba side, and +therefore was not counted correctly (the reason is that it often, depending on the PPD being used, wrote a +PJL-header in front of the real PostScript, which caused CUPS to skip <command>pstops</command> and go +directly to the <command>pstoraster</command> stage). +</para> + +<para> +From CUPS 1.1.16 and later releases, you can use the CUPS PostScript driver for Windows NT/200x/XP +clients (which is tagged in the download area of <filename>http://www.cups.org/</filename> as the +<filename>cups-samba-1.1.16.tar.gz</filename> package). It does <emphasis>not</emphasis> work for Windows +9x/Me clients, but it guarantees: +</para> + +<itemizedlist> + <listitem><para> <indexterm><primary>PJL</primary></indexterm> To not write a PJL-header.</para></listitem> + + <listitem><para>To still read and support all PJL-options named in the + driver PPD with its own means.</para></listitem> + + <listitem><para>That the file will pass through the <command>pstops</command> filter + on the CUPS/Samba server.</para></listitem> + + <listitem><para>To page-count correctly the print file.</para></listitem> +</itemizedlist> + +<para> +You can read more about the setup of this combination in the man page for <command>cupsaddsmb</command> (which +is only present with CUPS installed, and only current from CUPS 1.1.16). +</para> +</sect2> + +<sect2> +<title>The page_log File Syntax</title> + +<para> +<indexterm><primary>page_log</primary></indexterm> +These are the items CUPS logs in the <filename>page_log</filename> for every page of a job: +</para> + +<itemizedlist> + <listitem><para>Printer name</para></listitem> + + <listitem><para>User name</para></listitem> + + <listitem><para>Job ID</para></listitem> + + <listitem><para>Time of printing</para></listitem> + + <listitem><para>Page number</para></listitem> + + <listitem><para>Number of copies</para></listitem> + + <listitem><para>A billing information string (optional)</para></listitem> + + <listitem><para>The host that sent the job (included since version 1.1.19)</para></listitem> +</itemizedlist> + +<para> +Here is an extract of my CUPS server's <filename>page_log</filename> file to illustrate the +format and included items: +</para> + +<para><screen> +tec_IS2027 kurt 401 [22/Apr/2003:10:28:43 +0100] 1 3 #marketing 10.160.50.13 +tec_IS2027 kurt 401 [22/Apr/2003:10:28:43 +0100] 2 3 #marketing 10.160.50.13 +tec_IS2027 kurt 401 [22/Apr/2003:10:28:43 +0100] 3 3 #marketing 10.160.50.13 +tec_IS2027 kurt 401 [22/Apr/2003:10:28:43 +0100] 4 3 #marketing 10.160.50.13 +Dig9110 boss 402 [22/Apr/2003:10:33:22 +0100] 1 440 finance-dep 10.160.51.33 +</screen></para> + +<para> +This was job ID <parameter>401</parameter>, printed on <parameter>tec_IS2027</parameter> +by user <parameter>kurt</parameter>, a 64-page job printed in three copies, billed to +<parameter>#marketing</parameter>, and sent from IP address <constant>10.160.50.13.</constant> + The next job had ID <parameter>402</parameter>, was sent by user <parameter>boss</parameter> +from IP address <constant>10.160.51.33</constant>, printed from one page 440 copies, and +is set to be billed to <parameter>finance-dep</parameter>. +</para> +</sect2> + +<sect2> +<title>Possible Shortcomings</title> + +<para> +What flaws or shortcomings are there with this quota system? +</para> + +<itemizedlist> + <listitem><para>The ones named above (wrongly logged job in case of + printer hardware failure, and so on).</para></listitem> + + <listitem><para>In reality, CUPS counts the job pages that are being + processed in <emphasis>software</emphasis> (that is, going through the + RIP) rather than the physical sheets successfully leaving the + printing device. Thus, if there is a jam while printing the fifth sheet out + of 1,000 and the job is aborted by the printer, the page count will + still show the figure of 1,000 for that job.</para></listitem> + + <listitem><para>All quotas are the same for all users (no flexibility + to give the boss a higher quota than the clerk) and no support for + groups.</para></listitem> + + <listitem><para>No means to read out the current balance or the + <quote>used-up</quote> number of current quota.</para></listitem> + + <listitem><para>A user having used up 99 sheets of a 100 quota will + still be able to send and print a 1,000 sheet job.</para></listitem> + + <listitem><para>A user being denied a job because of a filled-up quota + does not get a meaningful error message from CUPS other than + <quote>client-error-not-possible</quote>.</para></listitem> +</itemizedlist> +</sect2> + +<sect2> +<title>Future Developments</title> + +<para> +This is the best system currently available, and there are huge +improvements under development for CUPS 1.2: +</para> + +<itemizedlist> + <listitem><para>Page counting will go into the backends (these talk + directly to the printer and will increase the count in sync with the + actual printing process; thus, a jam at the fifth sheet will lead to a + stop in the counting).</para></listitem> + + <listitem><para>Quotas will be handled more flexibly.</para></listitem> + + <listitem><para>Probably there will be support for users to inquire + about their accounts in advance.</para></listitem> + + <listitem><para>Probably there will be support for some other tools + around this topic.</para></listitem> +</itemizedlist> +</sect2> + +<sect2> +<title>Other Accounting Tools</title> + +<para> +Other accounting tools that can be used includes: PrintAnalyzer, pyKota, printbill, LogReport. +For more information regarding these tools you can try a Google search. +</para> + +</sect2> +</sect1> + +<sect1> +<title>Additional Material</title> + +<para> +A printer queue with <emphasis>no</emphasis> PPD associated to it is a +<quote>raw</quote> printer, and all files will go directly there as received by the +spooler. The exceptions are file types <parameter>application/octet-stream</parameter> +that need the pass-through feature enabled. <quote>Raw</quote> queues do not do any +filtering at all; they hand the file directly to the CUPS backend. +This backend is responsible for sending the data to the device +(as in the <quote>device URI</quote> notation: <filename>lpd://, socket://, +smb://, ipp://, http://, parallel:/, serial:/, usb:/</filename>, and so on). +</para> + +<para> +cupsomatic/Foomatic are <emphasis>not</emphasis> native CUPS drivers +and they do not ship with CUPS. They are a third-party add-on +developed at Linuxprinting.org. As such, they are a brilliant hack to +make all models (driven by Ghostscript drivers/filters in traditional +spoolers) also work via CUPS, with the same (good or bad!) quality as +in these other spoolers. <parameter>cupsomatic</parameter> is only a vehicle to execute a +Ghostscript command line at that stage in the CUPS filtering chain +where normally the native CUPS <parameter>pstoraster</parameter> filter would kick +in. <parameter>cupsomatic</parameter> bypasses <parameter>pstoraster</parameter>, kidnaps the print file from CUPS, +and redirects it to go through Ghostscript. CUPS accepts this +because the associated cupsomatic/foomatic-PPD specifies: + +<programlisting> +*cupsFilter: "application/vnd.cups-postscript 0 cupsomatic" +</programlisting> + +This line persuades CUPS to hand the file to <parameter>cupsomatic</parameter> once it has +successfully converted it to the MIME type +<parameter>application/vnd.cups-postscript</parameter>. This conversion will not happen for +jobs arriving from Windows that are autotyped +<parameter>application/octet-stream</parameter>, with the according changes in +<filename>/etc/cups/mime.types</filename> in place. +</para> + +<para> +CUPS is widely configurable and flexible, even regarding its filtering +mechanism. Another workaround in some situations would be to have in +<filename>/etc/cups/mime.types</filename> entries as follows: + +<programlisting> +application/postscript application/vnd.cups-raw 0 - +application/vnd.cups-postscript application/vnd.cups-raw 0 - +</programlisting> + +This would prevent all PostScript files from being filtered (rather, +they will through the virtual <emphasis>nullfilter</emphasis> +denoted with <quote>-</quote>). This could only be useful for PostScript printers. If you +want to print PostScript code on non-PostScript printers (provided they support ASCII +text printing), an entry as follows could be useful: + +<programlisting> +*/* application/vnd.cups-raw 0 - +</programlisting> + +and would effectively send <emphasis>all</emphasis> files to the +backend without further processing. +</para> + +<para> +You could have the following entry: + +<programlisting> +application/vnd.cups-postscript application/vnd.cups-raw 0 \ + my_PJL_stripping_filter +</programlisting> + +You will need to write a <parameter>my_PJL_stripping_filter</parameter> +(which could be a shell script) that parses the PostScript and removes the +unwanted PJL. This needs to conform to CUPS filter design +(mainly, receive and pass the parameters printername, job-id, +username, jobtitle, copies, print options, and possibly the +filename). It is installed as world executable into +<filename>/usr/lib/cups/filters/</filename> and is called by CUPS +if it encounters a MIME type <parameter>application/vnd.cups-postscript</parameter>. +</para> + +<para> +CUPS can handle <parameter>-o job-hold-until=indefinite</parameter>. +This keeps the job in the queue on hold. It will only be printed +upon manual release by the printer operator. This is a requirement in +many central reproduction departments, where a few operators manage +the jobs of hundreds of users on some big machine, where no user is +allowed to have direct access (such as when the operators often need +to load the proper paper type before running the 10,000 page job +requested by marketing for the mailing, and so on). +</para> +</sect1> + +<sect1> +<title>Autodeletion or Preservation of CUPS Spool Files</title> + +<para> +<indexterm><primary>/var/spool/samba</primary></indexterm> +<indexterm><primary>/var/spool/cups/</primary></indexterm> +<indexterm><primary>cupsd.conf</primary></indexterm> +Samba print files pass through two spool directories. One is the incoming directory managed by Samba (set in +the <smbconfoption name="path">/var/spool/samba</smbconfoption> directive in the <smbconfsection +name="[printers]"/> section of &smb.conf;). The other is the spool directory of your UNIX print subsystem. For +CUPS it is normally <filename>/var/spool/cups/</filename>, as set by the <filename>cupsd.conf</filename> +directive <filename>RequestRoot /var/spool/cups</filename>. +</para> + +<sect2> +<title>CUPS Configuration Settings Explained</title> + +<para> +Some important parameter settings in the CUPS configuration file +<filename>cupsd.conf</filename> are: +</para> + +<variablelist> + + <varlistentry><term>PreserveJobHistory Yes</term> + <listitem><para> + This keeps some details of jobs in cupsd's mind (well, it keeps the + c12345, c12346, and so on, files in the CUPS spool directory, which does a + similar job as the old-fashioned BSD-LPD control files). This is set + to <quote>Yes</quote> as a default. + </para></listitem></varlistentry> + + <varlistentry><term>PreserveJobFiles Yes</term> + <listitem><para> + This keeps the job files themselves in cupsd's mind + (it keeps the d12345, d12346, etc., files in the CUPS spool + directory). This is set to <quote>No</quote> as the CUPS + default. + </para></listitem></varlistentry> + + <varlistentry><term><quote>MaxJobs 500</quote></term> + <listitem><para> + This directive controls the maximum number of jobs + that are kept in memory. Once the number of jobs reaches the limit, + the oldest completed job is automatically purged from the system to + make room for the new one. If all of the known jobs are still + pending or active, then the new job will be rejected. Setting the + maximum to 0 disables this functionality. The default setting is + 0. + </para></listitem></varlistentry> +</variablelist> + +<para> +(There are also additional settings for <parameter>MaxJobsPerUser</parameter> and +<parameter>MaxJobsPerPrinter</parameter>.) +</para> +</sect2> + +<sect2> +<title>Preconditions</title> + +<para> +For everything to work as it should, you need to have three things: +</para> + +<itemizedlist> + <listitem><para>A Samba smbd that is compiled against <filename>libcups</filename> (check + on Linux by running <userinput>ldd `which smbd'</userinput>).</para></listitem> + + <listitem><para>A Samba-&smb.conf; setting of + <smbconfoption name="printing">cups</smbconfoption>.</para></listitem> + + <listitem><para>Another Samba &smb.conf; setting of + <smbconfoption name="printcap">cups</smbconfoption>.</para></listitem> +</itemizedlist> + +<note><para> +In this case, all other manually set printing-related commands (like +<smbconfoption name="print command"/>, +<smbconfoption name="lpq command"/>, +<smbconfoption name="lprm command"/>, +<smbconfoption name="lppause command"/>, and +<smbconfoption name="lpresume command"/>) are ignored, and they should normally have no +influence whatsoever on your printing. +</para></note> +</sect2> + +<sect2> +<title>Manual Configuration</title> + +<para> +If you want to do things manually, replace the <smbconfoption name="printing">cups</smbconfoption> +by <smbconfoption name="printing">bsd</smbconfoption>. Then your manually set commands may work +(I haven't tested this), and a <smbconfoption name="print command">lp -d %P %s; rm %s</smbconfoption> +may do what you need. +</para> +</sect2> +</sect1> + +<sect1> +<title>Printing from CUPS to Windows-Attached Printers</title> + +<para> +<indexterm><primary>smbspool</primary></indexterm> +<indexterm><primary>backends</primary></indexterm> +From time to time the question arises, how can you print <emphasis>to</emphasis> a Windows-attached printer +<emphasis>from</emphasis> Samba? Normally the local connection from Windows host to printer would be done by +USB or parallel cable, but this does not matter to Samba. From here only an SMB connection needs to be opened +to the Windows host. Of course, this printer must be shared first. As you have learned by now, CUPS uses +<emphasis>backends</emphasis> to talk to printers and other servers. To talk to Windows shared printers, you +need to use the <filename>smb</filename> (surprise, surprise!) backend. Check if this is in the CUPS backend +directory. This usually resides in <filename>/usr/lib/cups/backend/</filename>. You need to find an +<filename>smb</filename> file there. It should be a symlink to <filename>smbspool</filename>, and the file +must exist and be executable: +<screen> +&rootprompt;<userinput>ls -l /usr/lib/cups/backend/</userinput> +total 253 +drwxr-xr-x 3 root root 720 Apr 30 19:04 . +drwxr-xr-x 6 root root 125 Dec 19 17:13 .. +-rwxr-xr-x 1 root root 10692 Feb 16 21:29 canon +-rwxr-xr-x 1 root root 10692 Feb 16 21:29 epson +lrwxrwxrwx 1 root root 3 Apr 17 22:50 http -> ipp +-rwxr-xr-x 1 root root 17316 Apr 17 22:50 ipp +-rwxr-xr-x 1 root root 15420 Apr 20 17:01 lpd +-rwxr-xr-x 1 root root 8656 Apr 20 17:01 parallel +-rwxr-xr-x 1 root root 2162 Mar 31 23:15 pdfdistiller +lrwxrwxrwx 1 root root 25 Apr 30 19:04 ptal -> /usr/sbin/ptal-cups +-rwxr-xr-x 1 root root 6284 Apr 20 17:01 scsi +lrwxrwxrwx 1 root root 17 Apr 2 03:11 smb -> /usr/bin/smbspool +-rwxr-xr-x 1 root root 7912 Apr 20 17:01 socket +-rwxr-xr-x 1 root root 9012 Apr 20 17:01 usb + +&rootprompt;<userinput>ls -l `which smbspool`</userinput> +-rwxr-xr-x 1 root root 563245 Dec 28 14:49 /usr/bin/smbspool +</screen></para> + +<para> +If this symlink does not exist, create it: +<screen> +&rootprompt;<userinput>ln -s `which smbspool` /usr/lib/cups/backend/smb</userinput> +</screen></para> + +<para> +<indexterm><primary>smbspool</primary></indexterm> +<indexterm><primary>troubleshooting</primary></indexterm> +<command>smbspool</command> was written by Mike Sweet from the CUPS folks. It is included and ships with +Samba. It may also be used with print subsystems other than CUPS, to spool jobs to Windows printer shares. To +set up printer <replaceable>winprinter</replaceable> on CUPS, you need to have a driver for it. Essentially +this means to convert the print data on the CUPS/Samba host to a format that the printer can digest (the +Windows host is unable to convert any files you may send). This also means you should be able to print to the +printer if it were hooked directly at your Samba/CUPS host. For troubleshooting purposes, this is what you +should do to determine if that part of the process chain is in order. Then proceed to fix the network +connection/authentication to the Windows host, and so on. +</para> + +<para> +To install a printer with the <parameter>smb</parameter> backend on CUPS, use this command: +</para> + +<para><screen> +&rootprompt;<userinput>lpadmin -p winprinter -v smb://WINDOWSNETBIOSNAME/printersharename \ + -P /path/to/PPD</userinput> +</screen></para> + +<para> +<indexterm><primary>PostScript printers</primary></indexterm> +<indexterm><primary>PPD</primary></indexterm> +<indexterm><primary>Windows NT PostScript driver</primary></indexterm> +The PPD must be able to direct CUPS to generate the print data for the target model. For PostScript printers, +just use the PPD that would be used with the Windows NT PostScript driver. But what can you do if the printer +is only accessible with a password? Or if the printer's host is part of another workgroup? This is provided +for: You can include the required parameters as part of the <filename>smb://</filename> device-URI like this: +</para> + +<itemizedlist> + <listitem><para><filename>smb://WORKGROUP/WINDOWSNETBIOSNAME/printersharename</filename></para></listitem> + <listitem><para><filename>smb://username:password@WORKGROUP/WINDOWSNETBIOSNAME/printersharename</filename></para></listitem> + <listitem><para><filename>smb://username:password@WINDOWSNETBIOSNAME/printersharename</filename></para></listitem> +</itemizedlist> + +<para> +Note that the device URI will be visible in the process list of the Samba server (e.g., when someone uses the +<command>ps -aux</command> command on Linux), even if the username and passwords are sanitized before they get +written into the log files. This is an inherently insecure option; however, it is the only one. Don't use it +if you want to protect your passwords. Better share the printer in a way that does not require a password! +Printing will only work if you have a working NetBIOS name resolution up and running. Note that this is a +feature of CUPS and you do not necessarily need to have smbd running. + +</para> +</sect1> + +<sect1> +<title>More CUPS Filtering Chains</title> + +<para> +The diagrams in <link linkend="cups1">Filtering Chain 1</link> and <link linkend="cups2">Filtering Chain with +cupsomatic</link> show how CUPS handles print jobs. +</para> + +<figure id="cups1"> + <title>Filtering Chain 1.</title> + <imagefile>cups1</imagefile> +</figure> + +<!-- JJJ --> +<figure id="cups2"> + <title>Filtering Chain with cupsomatic</title> + <imagefile scale="45">cups2</imagefile> +</figure> + +</sect1> + +<sect1> +<title>Common Errors</title> + + <sect2> + <title>Windows 9x/Me Client Can't Install Driver</title> + + <para>For Windows 9x/Me, clients require the printer names to be eight + characters (or <quote>8 plus 3 chars suffix</quote>) max; otherwise, the driver files + will not get transferred when you want to download them from Samba.</para> + + </sect2> + + <sect2 id="root-ask-loop"> + <title><quote>cupsaddsmb</quote> Keeps Asking for Root Password in Never-ending Loop</title> + + <para>Have you set <smbconfoption name="security">user</smbconfoption>? Have + you used <command>smbpasswd</command> to give root a Samba account? + You can do two things: open another terminal and execute + <command>smbpasswd -a root</command> to create the account and + continue entering the password into the first terminal. Or, break + out of the loop by pressing Enter twice (without trying to type a + password).</para> + + <para> + If the error is <quote>Tree connect failed: NT_STATUS_BAD_NETWORK_NAME</quote>, + you may have forgotten to create the <filename>/etc/samba/drivers</filename> directory. + </para> + </sect2> + + <sect2> + <title><quote>cupsaddsmb</quote> or <quote>rpcclient addriver</quote> Emit Error</title> + + <para> + If <command>cupsaddsmb</command>, or <command>rpcclient addriver</command> emit the error message + WERR_BAD_PASSWORD, refer to <link linkend="root-ask-loop">the previous common error</link>. + </para> + + </sect2> + + <sect2> + <title><quote>cupsaddsmb</quote> Errors</title> + + <para> + The use of <quote>cupsaddsmb</quote> gives <quote>No PPD file for printer...</quote> + message while PPD file is present. What might the problem be? + </para> + + <para> + Have you enabled printer sharing on CUPS? This means, do you have a <literal><Location + /printers>....</Location></literal> section in CUPS server's <filename>cupsd.conf</filename> that + does not deny access to the host you run <quote>cupsaddsmb</quote> from? It <emphasis>could</emphasis> be an + issue if you use cupsaddsmb remotely, or if you use it with a <option>-h</option> parameter: + <userinput>cupsaddsmb -H sambaserver -h cupsserver -v printername</userinput>. + </para> + + <para>Is your <parameter>TempDir</parameter> directive in + <filename>cupsd.conf</filename> set to a valid value, and is it writable? + </para> + + </sect2> + + <sect2> + <title>Client Can't Connect to Samba Printer</title> + + <para>Use <command>smbstatus</command> to check which user + you are from Samba's point of view. Do you have the privileges to + write into the <smbconfsection name="[print$]"/> + share?</para> + + </sect2> + + <sect2> + <title>New Account Reconnection from Windows 200x/XP Troubles</title> + +<para> +Once you are connected as the wrong user (for example, as <constant>nobody</constant>, which often occurs if +you have <smbconfoption name="map to guest">bad user</smbconfoption>), Windows Explorer will not accept an +attempt to connect again as a different user. There will not be any bytes transferred on the wire to Samba, +but still you'll see a stupid error message that makes you think Samba has denied access. Use +<command>smbstatus</command> to check for active connections. Kill the PIDs. You still can't re-connect, and +you get the dreaded <computeroutput>You can't connect with a second account from the same +machine</computeroutput> message as soon as you try. And you do not see a single byte arriving at Samba (see +logs; use <quote>ethereal</quote>) indicating a renewed connection attempt. Shut all Explorer Windows. This +makes Windows forget what it has cached in its memory as established connections. Then reconnect as the right +user. The best method is to use a DOS terminal window and <emphasis>first</emphasis> do <userinput>net use z: +\\&example.server.samba;\print$ /user:root</userinput>. Check with <command>smbstatus</command> that you are +connected under a different account. Now open the <guilabel>Printers</guilabel> folder (on the Samba server in +the <guilabel>Network Neighborhood</guilabel>), right-click on the printer in question, and select +<guibutton>Connect....</guibutton>. +</para> +</sect2> + +<sect2> +<title>Avoid Being Connected to the Samba Server as the Wrong User</title> + +<para> +<indexterm><primary>smbstatus</primary></indexterm> +You see per <command>smbstatus</command> that you are connected as user nobody, but you want to be root or +printer admin. This is probably due to <smbconfoption name="map to guest">bad user</smbconfoption>, which +silently connected you under the guest account when you gave (maybe by accident) an incorrect username. Remove +<smbconfoption name="map to guest"/> if you want to prevent this. +</para> +</sect2> + +<sect2> +<title>Upgrading to CUPS Drivers from Adobe Drivers</title> + +<para> +This information came from a mailing list posting regarding problems experienced when +upgrading from Adobe drivers to CUPS drivers on Microsoft Windows NT/200x/XP clients. +</para> + +<para>First delete all old Adobe-using printers. Then delete all old Adobe drivers. (On Windows 200x/XP, right-click in +the background of <guilabel>Printers</guilabel> folder, select <guimenuitem>Server Properties...</guimenuitem>, select +tab <guilabel>Drivers</guilabel>, and delete here).</para> +</sect2> + +<sect2> +<title>Can't Use <quote>cupsaddsmb</quote> on Samba Server, Which Is a PDC</title> + +<para>Do you use the <quote>naked</quote> root user name? Try to do it +this way: <userinput>cupsaddsmb -U <replaceable>DOMAINNAME</replaceable>\\root -v +<replaceable>printername</replaceable></userinput>> (note the two backslashes: the first one is +required to <quote>escape</quote> the second one).</para> + +</sect2> + +<sect2> +<title>Deleted Windows 200x Printer Driver Is Still Shown</title> + +<para>Deleting a printer on the client will not delete the +driver too (to verify, right-click on the white background of the +<guilabel>Printers</guilabel> folder, select <guimenuitem>Server Properties</guimenuitem> and click on the +<guilabel>Drivers</guilabel> tab). These same old drivers will be re-used when you try to +install a printer with the same name. If you want to update to a new +driver, delete the old ones first. Deletion is only possible if no +other printer uses the same driver.</para> +</sect2> + +<sect2> +<title>Windows 200x/XP Local Security Policies</title> + +<indexterm><primary>Local security policies</primary></indexterm> +<indexterm><primary>unsigned drivers</primary></indexterm> +<para>Local security policies may not allow the installation of unsigned drivers &smbmdash; <quote>local +security policies</quote> may not allow the installation of printer drivers at all.</para> + +</sect2> + +<sect2> +<title>Administrator Cannot Install Printers for All Local Users</title> + +<para> +<indexterm><primary>SMB printers</primary></indexterm> +<indexterm><primary>IPP client</primary></indexterm> +Windows XP handles SMB printers on a <quote>per-user</quote> basis. +This means every user needs to install the printer himself or herself. To have a printer available for +everybody, you might want to use the built-in IPP client capabilities of Win XP. Add a printer with the print +path of <parameter>http://cupsserver:631/printers/printername</parameter>. We're still looking into this one. +Maybe a logon script could automatically install printers for all users. +</para> + +</sect2> + +<sect2> +<title>Print Change, Notify Functions on NT Clients</title> + +<para>For print change, notify functions on NT++ clients. These need to run the <command>Server</command> +service first (renamed to <command>File & Print Sharing for MS Networks</command> in XP).</para> + +</sect2> + +<sect2> +<title>Win XP-SP1</title> + +<para>Win XP-SP1 introduced a Point and Print Restriction Policy (this restriction does not apply to +<quote>Administrator</quote> or <quote>Power User</quote> groups of users). In Group Policy Object Editor, go +to <guimenu>User Configuration -> Administrative Templates -> Control Panel -> Printers</guimenu>. The policy +is automatically set to <constant>Enabled</constant> and the <constant>Users can only Point and Print to +machines in their Forest</constant> . You probably need to change it to <constant>Disabled</constant> or +<constant>Users can only Point and Print to these servers</constant> to make driver downloads from Samba +possible. +</para> +</sect2> + +<sect2> +<title>Print Options for All Users Can't Be Set on Windows 200x/XP</title> + +<para>How are you doing it? I bet the wrong way (it is not easy to find out, though). There are three +different ways to bring you to a dialog that <emphasis>seems</emphasis> to set everything. All three dialogs +<emphasis>look</emphasis> the same, yet only one of them does what you intend. You need to be Administrator or +Print Administrator to do this for all users. Here is how I do in on XP: +</para> + +<orderedlist numeration="upperalpha"> + + <listitem><para>The first wrong way: + + <orderedlist> + <listitem><para>Open the <guilabel>Printers</guilabel> + folder.</para></listitem> + + <listitem><para>Right-click on the printer + (<guilabel>remoteprinter on cupshost</guilabel>) and + select in context menu <guimenuitem>Printing + Preferences...</guimenuitem></para></listitem>. + + <listitem><para>Look at this dialog closely and remember what it looks like.</para></listitem> + </orderedlist> + </para></listitem> + + <listitem><para>The second wrong way: + <orderedlist> + <listitem><para>Open the <guilabel>Printers</guilabel> folder.</para></listitem> + + <listitem><para>Right-click on the printer (<guilabel>remoteprinter on + cupshost</guilabel>) and select the context menu + <guimenuitem>Properties</guimenuitem>.</para></listitem> + + <listitem><para>Click on the <guilabel>General</guilabel> tab.</para></listitem> + + <listitem><para>Click on the button <guibutton>Printing + Preferences...</guibutton></para></listitem>. + + <listitem><para>A new dialog opens. Keep this dialog open and go back + to the parent dialog.</para></listitem> + </orderedlist> + </para></listitem> + + <listitem><para>The third and correct way: + <orderedlist> + <listitem><para>Open the <guilabel>Printers</guilabel> folder.</para></listitem> + + <listitem><para>Right-click on the printer (<guilabel>remoteprinter on + cupshost</guilabel>) and select the context menu + <guimenuitem>Properties</guimenuitem>.</para></listitem> + + <listitem><para>Click on the <guilabel>Advanced</guilabel> + tab. (If everything is <quote>grayed out,</quote> then you are not logged + in as a user with enough privileges).</para></listitem> + + <listitem><para>Click on the <guibutton>Printing + Defaults...</guibutton> button.</para></listitem> + + <listitem><para>On any of the two new tabs, click on the + <guibutton>Advanced...</guibutton> button.</para></listitem> + + <listitem><para>A new dialog opens. Compare this one to the other + identical-looking one from step <quote>B.5</quote> or A.3".</para></listitem> + </orderedlist> + </para></listitem> +</orderedlist> + +<para> +Do you see any difference? I don't either. However, only the last one, which you arrived at with steps +<quote>C.1. to C.6.</quote>, will save any settings permanently and be the defaults for new users. If you want +all clients to get the same defaults, you need to conduct these steps <emphasis>as Administrator</emphasis> +(<smbconfoption name="printer admin"/> in &smb.conf;) <emphasis>before</emphasis> a client downloads the +driver (the clients can later set their own <emphasis>per-user defaults</emphasis> by following the procedures +<emphasis>A</emphasis> or <emphasis>B</emphasis>). +</para> + +</sect2> + +<sect2> +<title>Most Common Blunders in Driver Settings on Windows Clients</title> + +<para> +Don't use <parameter>Optimize for Speed</parameter>, but use <parameter>Optimize for Portability</parameter> +instead (Adobe PS Driver). Don't use <parameter>Page Independence: No</parameter>. Always settle with +<parameter>Page Independence: Yes</parameter> (Microsoft PS Driver and CUPS PS Driver for Windows NT/200x/XP). +If there are problems with fonts, use <parameter>Download as Softfont into printer</parameter> (Adobe PS +Driver). For <guilabel>TrueType Download Options</guilabel> choose <constant>Outline</constant>. Use +PostScript Level 2 if you are having trouble with a non-PS printer and if there is a choice. +</para> + +</sect2> + +<sect2> +<title><command>cupsaddsmb</command> Does Not Work with Newly Installed Printer</title> + +<para> +Symptom: The last command of <command>cupsaddsmb</command> does not complete successfully. If the <command>cmd += setdriver printername printername</command> result was NT_STATUS_UNSUCCESSFUL, then possibly the printer was +not yet recognized by Samba. Did it show up in Network Neighborhood? Did it show up in <command>rpcclient +hostname -c `enumprinters'</command>? Restart smbd (or send a <command>kill -HUP</command> to all processes +listed by <command>smbstatus</command>, and try again. +</para></sect2> + +<sect2> +<title>Permissions on <filename>/var/spool/samba/</filename> Get Reset After Each Reboot</title> + +<para> +Have you ever by accident set the CUPS spool directory to the same location (<parameter>RequestRoot +/var/spool/samba/</parameter> in <filename>cupsd.conf</filename> or the other way round: +<filename>/var/spool/cups/</filename> is set as <smbconfoption name="path"/>> in the <smbconfsection +name="[printers]"/> section)? These <parameter>must</parameter> be different. Set <parameter>RequestRoot +/var/spool/cups/</parameter> in <filename>cupsd.conf</filename> and <smbconfoption name="path"> +/var/spool/samba</smbconfoption> in the <smbconfsection name="[printers]"/> section of &smb.conf;. Otherwise, +cupsd will sanitize permissions to its spool directory with each restart and printing will not work reliably. +</para> + +</sect2> + +<sect2> +<title>Print Queue Called <quote>lp</quote> Mishandles Print Jobs</title> + +<para> +In this case a print queue called <quote>lp</quote> intermittently swallows jobs and +spits out completely different ones from what was sent. +</para> + +<para> +<indexterm><primary>lp</primary></indexterm> +<indexterm><primary>Implicit Classes</primary></indexterm> +<indexterm><primary>BrowseShortNames</primary></indexterm> +It is a bad idea to name any printer <quote>lp</quote>. This is the traditional UNIX name for the default +printer. CUPS may be set up to do an automatic creation of Implicit Classes. This means, to group all printers +with the same name to a pool of devices and load-balance the jobs across them in a round-robin fashion. +Chances are high that someone else has a printer named <quote>lp</quote> too. You may receive that person's +jobs and send your own to his or her device unwittingly. To have tight control over the printer names, set +<parameter>BrowseShortNames No</parameter>. It will present any printer as +<replaceable>printername@cupshost</replaceable>, which gives you better control over what may happen in a +large networked environment. +</para> + +</sect2> + +<sect2> +<title>Location of Adobe PostScript Driver Files for <quote>cupsaddsmb</quote></title> + +<para> +Use <command>smbclient</command> to connect to any Windows box with a shared PostScript printer: +<command>smbclient //windowsbox/print\$ -U guest</command>. You can navigate to the +<filename>W32X86/2</filename> subdir to <command>mget ADOBE*</command> and other files or to +<filename>WIN40/0</filename> to do the same. Another option is to download the <filename>*.exe</filename> +packaged files from the Adobe Web site. +</para> + +</sect2> + +</sect1> + +<sect1> +<title>Overview of the CUPS Printing Processes</title> + +<para> +A complete overview of the CUPS printing processes can be found in <link linkend="a_small">the CUPS +Printing Overview diagram</link>. +</para> + +<figure id="a_small"> + <title>CUPS Printing Overview.</title> + <imagefile scale="45">a_small</imagefile> +</figure> +</sect1> + +</chapter> |