1<!--$Id: env_set_errfile.so,v 10.37 2006/10/26 15:33:59 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: DB_ENV->set_errfile</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>DB_ENV->set_errfile</b> 14</td> 15<td align=right> 16<a href="/api_c/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.h> 23<p> 24void 25DB_ENV->set_errfile(DB_ENV *dbenv, FILE *errfile); 26<p> 27void 28DB_ENV->get_errfile(DB_ENV *dbenv, FILE **errfilep); 29</pre></b> 30<hr size=1 noshade> 31<b>Description: DB_ENV->set_errfile</b> 32When an error occurs in the Berkeley DB library, a Berkeley DB error or an error 33return value is returned by the interface. In some cases, however, the 34return value may be insufficient to completely describe the cause of the 35error especially during initial application debugging. 36<p>The DB_ENV->set_errfile and <a href="/api_c/db_set_errfile.html">DB->set_errfile</a> methods are used to 37enhance the mechanism for reporting error messages to the application 38by setting a C library FILE * to be used for displaying additional Berkeley DB 39error messages. In some cases, when an error occurs, Berkeley DB will output 40an additional error message to the specified file reference.</p> 41<p>The error message will consist of the prefix string and a colon 42("<b>:</b>") (if a prefix string was previously specified using 43<a href="/api_c/db_set_errpfx.html">DB->set_errpfx</a> or <a href="/api_c/env_set_errpfx.html">DB_ENV->set_errpfx</a>), an error string, and 44a trailing <newline> character.</p> 45<p>The default configuration when applications first create <a href="/api_c/db_class.html">DB</a> or 46<a href="/api_c/env_class.html">DB_ENV</a> handles is as if the DB_ENV->set_errfile or 47<a href="/api_c/db_set_errfile.html">DB->set_errfile</a> methods were called with the standard error output 48(stderr) specified as the FILE * argument. Applications wanting no 49output at all can turn off this default configuration by calling the 50DB_ENV->set_errfile or <a href="/api_c/db_set_errfile.html">DB->set_errfile</a> methods with NULL as the 51FILE * argument. Additionally, explicitly configuring the error output 52channel using any of the DB_ENV->set_errfile, 53<a href="/api_c/db_set_errfile.html">DB->set_errfile</a>, <a href="/api_c/env_set_errcall.html">DB_ENV->set_errcall</a>, 54<a href="/api_c/db_set_errcall.html">DB->set_errcall</a>, <a href="/api_cxx/env_set_error_stream.html">DbEnv::set_error_stream</a> or 55<a href="/api_cxx/db_set_error_stream.html">Db::set_error_stream</a> methods will also turn off this default output 56for the application.</p> 57<p>This error logging enhancement does not slow performance or significantly 58increase application size, and may be run during normal operation as well 59as during application debugging.</p> 60<p>The DB_ENV->set_errfile method configures operations performed using the specified 61<a href="/api_c/env_class.html">DB_ENV</a> handle, not all operations performed on the underlying 62database environment.</p> 63<p>The DB_ENV->set_errfile method may be called at any time during the life of the 64application.</p> 65<b>Parameters</b> <br> 66 <b>errfile</b><ul compact><li>The <b>errfile</b> parameter is a C library FILE * to be used for 67displaying additional Berkeley DB error information.</ul> 68<br> 69<hr size=1 noshade> 70<b>Description: DB_ENV->get_errfile</b> 71<p>The DB_ENV->get_errfile method returns the FILE *.</p> 72<p>The DB_ENV->get_errfile method may be called at any time during the life of the 73application.</p> 74<p>The DB_ENV->get_errfile method 75returns a non-zero error value on failure 76and 0 on success. 77</p> 78<b>Parameters</b> <br> 79 <b>errfilep</b><ul compact><li>The DB_ENV->get_errfile method returns the 80FILE * in <b>errfilep</b>.</ul> 81<br> 82<hr size=1 noshade> 83<br><b>Class</b> 84<a href="/api_c/env_class.html">DB_ENV</a> 85<br><b>See Also</b> 86<a href="/api_c/env_list.html">Database Environments and Related Methods</a> 87</tt> 88<table width="100%"><tr><td><br></td><td align=right> 89<a href="/api_c/api_core.html"><img src="/images/api.gif" alt="API"></a><a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a> 90</td></tr></table> 91<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 92</body> 93</html> 94
