1<!--$Id: db_set_errfile.so,v 10.10 2002/08/18 21:15:54 bostic Exp $--> 2<!--$Id: env_set_errfile.so,v 10.37 2006/10/26 15:33:59 bostic Exp $--> 3<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 4<!--See the file LICENSE for redistribution information.--> 5<html> 6<head> 7<title>Berkeley DB: DB->set_errfile</title> 8<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 9<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 10</head> 11<body bgcolor=white> 12<table width="100%"><tr valign=top> 13<td> 14<b>DB->set_errfile</b> 15</td> 16<td align=right> 17<a href="/api_c/api_core.html"><img src="/images/api.gif" alt="API"></a> 18<a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a></td> 19</tr></table> 20<hr size=1 noshade> 21<tt> 22<b><pre> 23#include <db.h> 24<p> 25void 26DB->set_errfile(DB *db, FILE *errfile); 27<p> 28void 29DB->get_errfile(DB *db, FILE **errfilep); 30</pre></b> 31<hr size=1 noshade> 32<b>Description: DB->set_errfile</b> 33When an error occurs in the Berkeley DB library, a Berkeley DB error or an error 34return value is returned by the interface. In some cases, however, the 35return value may be insufficient to completely describe the cause of the 36error especially during initial application debugging. 37<p>The <a href="/api_c/env_set_errfile.html">DB_ENV->set_errfile</a> and DB->set_errfile methods are used to 38enhance the mechanism for reporting error messages to the application 39by setting a C library FILE * to be used for displaying additional Berkeley DB 40error messages. In some cases, when an error occurs, Berkeley DB will output 41an additional error message to the specified file reference.</p> 42<p>The error message will consist of the prefix string and a colon 43("<b>:</b>") (if a prefix string was previously specified using 44<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 45a trailing <newline> character.</p> 46<p>The default configuration when applications first create <a href="/api_c/db_class.html">DB</a> or 47<a href="/api_c/env_class.html">DB_ENV</a> handles is as if the <a href="/api_c/env_set_errfile.html">DB_ENV->set_errfile</a> or 48DB->set_errfile methods were called with the standard error output 49(stderr) specified as the FILE * argument. Applications wanting no 50output at all can turn off this default configuration by calling the 51<a href="/api_c/env_set_errfile.html">DB_ENV->set_errfile</a> or DB->set_errfile methods with NULL as the 52FILE * argument. Additionally, explicitly configuring the error output 53channel using any of the <a href="/api_c/env_set_errfile.html">DB_ENV->set_errfile</a>, 54DB->set_errfile, <a href="/api_c/env_set_errcall.html">DB_ENV->set_errcall</a>, 55<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 56<a href="/api_cxx/db_set_error_stream.html">Db::set_error_stream</a> methods will also turn off this default output 57for the application.</p> 58<p>This error logging enhancement does not slow performance or significantly 59increase application size, and may be run during normal operation as well 60as during application debugging.</p> 61<p>For <a href="/api_c/db_class.html">DB</a> handles opened inside of Berkeley DB environments, calling the 62DB->set_errfile method affects the entire environment and is equivalent to calling 63the <a href="/api_c/env_set_errfile.html">DB_ENV->set_errfile</a> method.</p> 64<p>The DB->set_errfile method configures operations performed using the specified 65<a href="/api_c/db_class.html">DB</a> handle, not all operations performed on the underlying 66database.</p> 67<p>The DB->set_errfile method may be called at any time during the life of the 68application.</p> 69<b>Parameters</b> <br> 70 <b>errfile</b><ul compact><li>The <b>errfile</b> parameter is a C library FILE * to be used for 71displaying additional Berkeley DB error information.</ul> 72<br> 73<hr size=1 noshade> 74<b>Description: DB->get_errfile</b> 75<p>The DB->get_errfile method returns the FILE *.</p> 76<p>The DB->get_errfile method may be called at any time during the life of the 77application.</p> 78<p>The DB->get_errfile method 79returns a non-zero error value on failure 80and 0 on success. 81</p> 82<b>Parameters</b> <br> 83 <b>errfilep</b><ul compact><li>The DB->get_errfile method returns the 84FILE * in <b>errfilep</b>.</ul> 85<br> 86<hr size=1 noshade> 87<br><b>Class</b> 88<a href="/api_c/db_class.html">DB</a> 89<br><b>See Also</b> 90<a href="/api_c/db_list.html">Databases and Related Methods</a> 91</tt> 92<table width="100%"><tr><td><br></td><td align=right> 93<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> 94</td></tr></table> 95<p><font size=1>Copyright (c) 1996,2008 Oracle. 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