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diff --git a/db/docs/ref/env/error.html b/db/docs/ref/env/error.html new file mode 100644 index 000000000..1a79d8fe5 --- /dev/null +++ b/db/docs/ref/env/error.html @@ -0,0 +1,57 @@ +<!--$Id: error.so,v 10.13 2001/01/11 15:23:14 bostic Exp $--> +<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> +<!--All rights reserved.--> +<html> +<head> +<title>Berkeley DB Reference Guide: Error support</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>Environment</dl></h3></td> +<td width="1%"><a href="../../ref/env/open.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/cam/intro.html"><img src="../../images/next.gif" alt="Next"></a> +</td></tr></table> +<p> +<h1 align=center>Error support</h1> +<p>Berkeley DB offers programmatic support for displaying error return values. +The <a href="../../api_c/env_strerror.html">db_strerror</a> interface returns a pointer to the error +message corresponding to any Berkeley DB error return, similar to the ANSI C +strerror interface, but able to handle both system error returns and +Berkeley DB specific return values. +<p>For example: +<p><blockquote><pre>int ret; +if ((ret = dbenv->set_cachesize(dbenv, 0, 32 * 1024)) != 0) { + fprintf(stderr, "set_cachesize failed: %s\n", db_strerror(ret)); + return (1); +}</pre></blockquote> +<p>There are also two additional error functions, <a href="../../api_c/db_err.html">DBENV->err</a> and +<a href="../../api_c/db_err.html">DBENV->errx</a>. These functions work like the ANSI C printf +interface, taking a printf-style format string and argument list, and +writing a message constructed from the format string and arguments. +<p>The <a href="../../api_c/db_err.html">DBENV->err</a> function appends the standard error string to the +constructed message and the <a href="../../api_c/db_err.html">DBENV->errx</a> function does not. +<p>Error messages can be configured always to include a prefix (e.g., the +program name) using the <a href="../../api_c/env_set_errpfx.html">DBENV->set_errpfx</a> interface. +<p>These functions provide simpler ways of displaying Berkeley DB error messages: +<p><blockquote><pre>int ret; +dbenv->set_errpfx(dbenv, argv0); +if ((ret = dbenv->open(dbenv, home, NULL, + DB_CREATE | DB_INIT_LOG | DB_INIT_TXN | DB_USE_ENVIRON)) + != 0) { + dbenv->err(dbenv, ret, "open: %s", home); + dbenv->errx(dbenv, + "contact your system administrator: session ID was %d", + session_id); + return (1); +}</pre></blockquote> +<p>For example, if the program was called "my_app", attempting to open an +environment home directory in "/tmp/home", and the open call returned a +permission error, the error messages shown would look like: +<p><blockquote><pre>my_app: open: /tmp/home: Permission denied. +my_app: contact your system administrator: session ID was 2</pre></blockquote> +<table><tr><td><br></td><td width="1%"><a href="../../ref/env/open.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/cam/intro.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> |