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diff --git a/APACHE_1_3_42/htdocs/manual/mod/mod_mime_magic.html b/APACHE_1_3_42/htdocs/manual/mod/mod_mime_magic.html new file mode 100644 index 0000000000..3a5a76befb --- /dev/null +++ b/APACHE_1_3_42/htdocs/manual/mod/mod_mime_magic.html @@ -0,0 +1,326 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml"> + <head> + <meta name="generator" content="HTML Tidy, see www.w3.org" /> + + <title>Apache module mod_mime_magic</title> + </head> + <!-- Background white, links blue (unvisited), navy (visited), red (active) --> + + <body bgcolor="#FFFFFF" text="#000000" link="#0000FF" + vlink="#000080" alink="#FF0000"> + <div align="CENTER"> + <img src="../images/sub.gif" alt="[APACHE DOCUMENTATION]" /> + </div> + + <h1 align="CENTER">Module mod_mime_magic</h1> + + <p>This module provides for determining the MIME type of a file + by looking at a few bytes of its contents.</p> + + <p><a href="module-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Extension<br /> + <a href="module-dict.html#SourceFile" + rel="Help"><strong>Source File:</strong></a> + mod_mime_magic.c<br /> + <a href="module-dict.html#ModuleIdentifier" + rel="Help"><strong>Module Identifier:</strong></a> + mime_magic_module</p> + + <h2>Summary</h2> + + <p>This module determines the MIME type of files in the same + way the Unix file(1) command works: it looks at the first few + bytes of the file. It is intended as a "second line of defense" + for cases that <a href="mod_mime.html">mod_mime</a> can't + resolve. To assure that mod_mime gets first try at determining + a file's MIME type, be sure to list mod_mime_magic + <strong>before</strong> mod_mime in the configuration.</p> + + <p>This module is derived from a free version of the + <code>file(1)</code> command for Unix, which uses "magic + numbers" and other hints from a file's contents to figure out + what the contents are. This module is active only if the magic + file is specified by the <a + href="#mimemagicfile"><code>MimeMagicFile</code></a> + directive.</p> + + <h2>Directives</h2> + + <ul> + <li><a href="#mimemagicfile">MimeMagicFile</a></li> + </ul> + + <h2>Format of the Magic File</h2> + + <p>The contents of the file are plain ASCII text in 4-5 + columns. Blank lines are allowed but ignored. Commented lines + use a hash mark "#". The remaining lines are parsed for the + following columns:</p> + + <table border="1"> + <tr valign="top"> + <th>Column</th> + + <th>Description</th> + </tr> + + <tr valign="top"> + <td>1</td> + + <td>byte number to begin checking from<br /> + ">" indicates a dependency upon the previous non-">" + line</td> + </tr> + + <tr valign="top"> + <td>2</td> + + <td> + type of data to match + + <table border="1"> + <tr> + <td>byte</td> + + <td>single character</td> + </tr> + + <tr> + <td>short</td> + + <td>machine-order 16-bit integer</td> + </tr> + + <tr> + <td>long</td> + + <td>machine-order 32-bit integer</td> + </tr> + + <tr> + <td>string</td> + + <td>arbitrary-length string</td> + </tr> + + <tr> + <td>date</td> + + <td>long integer date (seconds since Unix + epoch/1970)</td> + </tr> + + <tr> + <td>beshort</td> + + <td>big-endian 16-bit integer</td> + </tr> + + <tr> + <td>belong</td> + + <td>big-endian 32-bit integer</td> + </tr> + + <tr> + <td>bedate</td> + + <td>big-endian 32-bit integer date</td> + </tr> + + <tr> + <td>leshort</td> + + <td>little-endian 16-bit integer</td> + </tr> + + <tr> + <td>lelong</td> + + <td>little-endian 32-bit integer</td> + </tr> + + <tr> + <td>ledate</td> + + <td>little-endian 32-bit integer date</td> + </tr> + </table> + </td> + </tr> + + <tr valign="top"> + <td>3</td> + + <td>contents of data to match</td> + </tr> + + <tr valign="top"> + <td>4</td> + + <td>MIME type if matched</td> + </tr> + + <tr valign="top"> + <td>5</td> + + <td>MIME encoding if matched (optional)</td> + </tr> + </table> + + <p>For example, the following magic file lines would recognize + some audio formats.</p> +<pre> +# Sun/NeXT audio data +0 string .snd +>12 belong 1 audio/basic +>12 belong 2 audio/basic +>12 belong 3 audio/basic +>12 belong 4 audio/basic +>12 belong 5 audio/basic +>12 belong 6 audio/basic +>12 belong 7 audio/basic +>12 belong 23 audio/x-adpcm +</pre> + Or these would recognize the difference between "*.doc" files + containing Microsoft Word or FrameMaker documents. (These are + incompatible file formats which use the same file suffix.) +<pre> +# Frame +0 string \<MakerFile application/x-frame +0 string \<MIFFile application/x-frame +0 string \<MakerDictionary application/x-frame +0 string \<MakerScreenFon application/x-frame +0 string \<MML application/x-frame +0 string \<Book application/x-frame +0 string \<Maker application/x-frame + +# MS-Word +0 string \376\067\0\043 application/msword +0 string \320\317\021\340\241\261 application/msword +0 string \333\245-\0\0\0 application/msword +</pre> + An optional MIME encoding can be included as a fifth column. + For example, this can recognize gzipped files and set the + encoding for them. +<pre> +# gzip (GNU zip, not to be confused with [Info-ZIP/PKWARE] zip archiver) +0 string \037\213 application/octet-stream x-gzip +</pre> + + <h2>Performance Issues</h2> + This module is not for every system. If your system is barely + keeping up with its load or if you're performing a web server + benchmark, you may not want to enable this because the + processing is not free. + + <p>However, an effort was made to improve the performance of + the original file(1) code to make it fit in a busy web server. + It was designed for a server where there are thousands of users + who publish their own documents. This is probably very common + on intranets. Many times, it's helpful if the server can make + more intelligent decisions about a file's contents than the + file name allows ...even if just to reduce the "why doesn't my + page work" calls when users improperly name their own files. + You have to decide if the extra work suits your + environment.</p> + + <p>When compiling an Apache server, this module should be at or + near the top of the list of modules in the Configuration file. + The modules are listed in increasing priority so that will mean + this one is used only as a last resort, just like it was + designed to.</p> + + <h2><a id="notes" name="notes">Notes</a></h2> + The following notes apply to the mod_mime_magic module and are + included here for compliance with contributors' copyright + restrictions that require their acknowledgment. +<pre> +/* + * mod_mime_magic: MIME type lookup via file magic numbers + * Copyright (c) 1996-1997 Cisco Systems, Inc. + * + * This software was submitted by Cisco Systems to the Apache Group in July + * 1997. Future revisions and derivatives of this source code must + * acknowledge Cisco Systems as the original contributor of this module. + * All other licensing and usage conditions are those of the Apache Group. + * + * Some of this code is derived from the free version of the file command + * originally posted to comp.sources.unix. Copyright info for that program + * is included below as required. + * --------------------------------------------------------------------------- + * - Copyright (c) Ian F. Darwin, 1987. Written by Ian F. Darwin. + * + * This software is not subject to any license of the American Telephone and + * Telegraph Company or of the Regents of the University of California. + * + * Permission is granted to anyone to use this software for any purpose on any + * computer system, and to alter it and redistribute it freely, subject to + * the following restrictions: + * + * 1. The author is not responsible for the consequences of use of this + * software, no matter how awful, even if they arise from flaws in it. + * + * 2. The origin of this software must not be misrepresented, either by + * explicit claim or by omission. Since few users ever read sources, credits + * must appear in the documentation. + * + * 3. Altered versions must be plainly marked as such, and must not be + * misrepresented as being the original software. Since few users ever read + * sources, credits must appear in the documentation. + * + * 4. This notice may not be removed or altered. + * ------------------------------------------------------------------------- + * + * For compliance with Mr Darwin's terms: this has been very significantly + * modified from the free "file" command. + * - all-in-one file for compilation convenience when moving from one + * version of Apache to the next. + * - Memory allocation is done through the Apache API's pool structure. + * - All functions have had necessary Apache API request or server + * structures passed to them where necessary to call other Apache API + * routines. (<em>i.e.</em>, usually for logging, files, or memory allocation in + * itself or a called function.) + * - struct magic has been converted from an array to a single-ended linked + * list because it only grows one record at a time, it's only accessed + * sequentially, and the Apache API has no equivalent of realloc(). + * - Functions have been changed to get their parameters from the server + * configuration instead of globals. (It should be reentrant now but has + * not been tested in a threaded environment.) + * - Places where it used to print results to stdout now saves them in a + * list where they're used to set the MIME type in the Apache request + * record. + * - Command-line flags have been removed since they will never be used here. + * + */ +</pre> + <hr /> + + <h2><a id="mimemagicfile" + name="mimemagicfile">MimeMagicFile</a></h2> + + <p><a href="directive-dict.html#Syntax" + rel="Help"><strong>Syntax:</strong></a> MimeMagicFile + <em>file-path</em><br /> + <a href="directive-dict.html#Default" + rel="Help"><strong>Default:</strong></a> none<br /> + <a href="directive-dict.html#Context" + rel="Help"><strong>Context:</strong></a> server config, virtual + host<br /> + <a href="directive-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Extension<br /> + <a href="directive-dict.html#Module" + rel="Help"><strong>Module:</strong></a> mod_mime_magic</p> + + <p>The <code>MimeMagicFile</code> directive can be used to + enable this module, the default file is distributed at + <code>conf/magic</code>. Non-rooted paths are relative to the + ServerRoot. Virtual hosts will use the same file as the main + server unless a more specific setting is used, in which case + the more specific setting overrides the main server's file.</p> + </body> +</html> + |