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diff --git a/bdb/docs/ref/tcl/error.html b/bdb/docs/ref/tcl/error.html deleted file mode 100644 index 3d1de037d52..00000000000 --- a/bdb/docs/ref/tcl/error.html +++ /dev/null @@ -1,69 +0,0 @@ -<!--$Id: error.so,v 11.13 2001/01/09 18:48:06 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Tcl error handling</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> -</head> -<body bgcolor=white> -<table><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Tcl</dl></h3></td> -<td width="1%"><a href="../../ref/tcl/program.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/tcl/faq.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h1 align=center>Tcl error handling</h1> -<p>The Tcl interfaces to Berkeley DB generally return TCL_OK on success and throw -a Tcl error on failure, using the appropriate Tcl interfaces to provide -the user with an informative error message. There are some "expected" -failures, however, for which no Tcl error will be thrown and for which -Tcl commands will return TCL_OK. These failures include when a -searched-for key is not found, a requested key/data pair was previously -deleted, or a key/data pair cannot be written because the key already -exists. -<p>These failures can be detected by searching the Berkeley DB error message that -is returned. For example, to detect that an attempt to put a record into -the database failed because the key already existed: -<p><blockquote><pre>% berkdb open -create -btree a.db -db0 -% db0 put dog cat -0 -% set ret [db0 put -nooverwrite dog newcat] -DB_KEYEXIST: Key/data pair already exists -% if { [string first DB_KEYEXIST $ret] != -1 } { - puts "This was an error; the key existed" -} -This was an error; the key existed -% db0 close -0 -% exit</pre></blockquote> -<p>To simplify parsing, it is recommended that the initial Berkeley DB error name -be checked, e.g., DB_KEYEXIST in the above example. These values will -not change in future releases of Berkeley DB to ensure that Tcl scripts are not -broken by upgrading to new releases of Berkeley DB. There are currently only -three such "expected" error returns. They are: -<p><blockquote><pre>DB_NOTFOUND: No matching key/data pair found -DB_KEYEMPTY: Non-existent key/data pair -DB_KEYEXIST: Key/data pair already exists</pre></blockquote> -<p>Finally, in some cases, when a Berkeley DB error occurs Berkeley DB will output -additional error information. By default, all Berkeley DB error messages will -be prefixed with the created command in whose context the error occurred -(e.g., "env0", "db2", etc.). There are several ways to capture and -access this information. -<p>First, if Berkeley DB invokes the error callback function, the additional -information will be placed in the error result returned from the -command and in the errorInfo backtrace variable in Tcl. -<p>Also the two calls to open an environment and -open a database take an option, <b>-errfile filename</b>, which sets an -output file to which these additional error messages should be written. -<p>Additionally the two calls to open an environment and -open a database take an option, <b>-errpfx string</b>, which sets the -error prefix to the given string. This option may be useful -in circumstances where a more descriptive prefix is desired or -where a constant prefix indicating an error is desired. -<table><tr><td><br></td><td width="1%"><a href="../../ref/tcl/program.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/tcl/faq.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |