1<!--$Id: env_err.so,v 10.34 2006/04/27 20:17:47 bostic Exp $--> 2<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 3<!--See the file LICENSE for redistribution information.--> 4<html> 5<head> 6<title>Berkeley DB: DbEnv::err</title> 7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 9</head> 10<body bgcolor=white> 11<table width="100%"><tr valign=top> 12<td> 13<b>DbEnv::err</b> 14</td> 15<td align=right> 16<a href="/api_cxx/api_core.html"><img src="/images/api.gif" alt="API"></a> 17<a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a></td> 18</tr></table> 19<hr size=1 noshade> 20<tt> 21<b><pre> 22#include <db_cxx.h> 23<p> 24DbEnv::err(int error, const char *fmt, ...); 25<p> 26DbEnv::errx(const char *fmt, ...); 27</pre></b> 28<hr size=1 noshade> 29<b>Description: DbEnv::err</b> 30<p>The DbEnv::err, DbEnv::errx, <a href="/api_cxx/db_err.html">Db::err</a> and 31<a href="/api_cxx/db_err.html">Db::errx</a> methods provide error-messaging functionality for 32applications written using the Berkeley DB library.</p> 33<p>The <a href="/api_cxx/db_err.html">Db::err</a> and DbEnv::err methods constructs an error message 34consisting of the following elements:</p> 35<blockquote><br> 36<b>An optional prefix string</b><ul compact><li>If no error callback function has been set using the 37<a href="/api_cxx/env_set_errcall.html">DbEnv::set_errcall</a> method, any prefix string specified using the 38<a href="/api_cxx/env_set_errpfx.html">DbEnv::set_errpfx</a> method, followed by two separating characters: a colon 39and a <space> character.</ul> 40<b>An optional printf-style message</b><ul compact><li>The supplied message <b>fmt</b>, if non-NULL, in which the 41ANSI C X3.159-1989 (ANSI C) printf function specifies how subsequent parameters 42are converted for output.</ul> 43<b>A separator</b><ul compact><li>Two separating characters: a colon and a <space> character.</ul> 44<b>A standard error string</b><ul compact><li>The standard system or Berkeley DB library error string associated with the 45<b>error</b> value, as returned by the <a href="/api_cxx/env_strerror.html">DbEnv::strerror</a> method.</ul> 46<br> 47</blockquote> 48<p>The <a href="/api_cxx/db_err.html">Db::errx</a> and DbEnv::errx methods are the same as the 49<a href="/api_cxx/db_err.html">Db::err</a> and DbEnv::err methods, except they do not append the 50final separator characters and standard error string to the error 51message.</p> 52<p>This constructed error message is then handled as follows:</p> 53<blockquote><p>If an error callback function has been set (see <a href="/api_cxx/db_set_errcall.html">Db::set_errcall</a> 54and <a href="/api_cxx/env_set_errcall.html">DbEnv::set_errcall</a>), that function is called with two 55parameters: any prefix string specified (see <a href="/api_cxx/db_set_errpfx.html">Db::set_errpfx</a> and 56<a href="/api_cxx/env_set_errpfx.html">DbEnv::set_errpfx</a>) and the error message.</p> 57<p>If a C library FILE * has been set (see <a href="/api_cxx/db_set_errfile.html">Db::set_errfile</a> and 58<a href="/api_cxx/env_set_errfile.html">DbEnv::set_errfile</a>), the error message is written to that output 59stream.</p> 60<p>If a C++ ostream has been set 61(see <a href="/api_cxx/env_set_error_stream.html">DbEnv::set_error_stream</a> and <a href="/api_cxx/db_set_error_stream.html">Db::set_error_stream</a>), 62the error message is written to that stream.</p> 63<p>If none of these output options has been configured, the error message 64is written to stderr, the standard error output stream.</p></blockquote> 65<b>Parameters</b> <br> 66 <b>error</b><ul compact><li>The <b>error</b> parameter is the error value for which the 67DbEnv::err and <a href="/api_cxx/db_err.html">Db::err</a> methods will display a explanatory 68string.</ul> 69 <b>fmt</b><ul compact><li>The <b>fmt</b> parameter is an optional printf-style message to display.</ul> 70<br> 71<hr size=1 noshade> 72<br><b>Class</b> 73<a href="/api_cxx/env_class.html">DbEnv</a> 74<br><b>See Also</b> 75<a href="/api_cxx/env_list.html">Database Environments and Related Methods</a> 76</tt> 77<table width="100%"><tr><td><br></td><td align=right> 78<a href="/api_cxx/api_core.html"><img src="/images/api.gif" alt="API"></a><a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a> 79</td></tr></table> 80<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 81</body> 82</html> 83
