1<!--$Id: env_set_feedback.so,v 10.43 2006/05/17 20:47:46 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_feedback</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_feedback</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> 24int 25DB_ENV->set_feedback(DB_ENV *dbenv, 26 void (*db_feedback_fcn)(DB_ENV *dbenv, int opcode, int percent)); 27</pre></b> 28<hr size=1 noshade> 29<b>Description: DB_ENV->set_feedback</b> 30<p>Some operations performed by the Berkeley DB library can take non-trivial 31amounts of time. The DB_ENV->set_feedback method can be used by applications 32to monitor progress within these operations. When an operation is 33likely to take a long time, Berkeley DB will call the specified callback 34function with progress information.</p> 35<p>It is up to the callback function to display this information in an 36appropriate manner.</p> 37<p>The DB_ENV->set_feedback method configures operations performed using the specified 38<a href="../api_c/env_class.html">DB_ENV</a> handle 39<p>The DB_ENV->set_feedback method may be called at any time during the life of the 40application.</p> 41<p>The DB_ENV->set_feedback method 42returns a non-zero error value on failure 43and 0 on success. 44</p> 45<b>Parameters</b> <br> 46 <b>db_feedback_fcn</b><ul compact><li>The <b>db_feedback_fcn</b> parameter is the application-specified 47feedback function called to report Berkeley DB operation progress. The 48callback function must take three parameters: 49<br> 50<b><b>dbenv</b></b><ul compact><li>The <b>dbenv</b> parameter is a reference to the enclosing database 51environment.</ul> 52<b><b>opcode</b></b><ul compact><li>The <b>opcode</b> parameter is an operation code. The <b>opcode</b> 53parameter may take on any of the following values: 54<br> 55<b><a name="DB_RECOVER">DB_RECOVER</a></b><ul compact><li>The environment is being recovered.</ul> 56<br></ul> 57<b><b>percent</b></b><ul compact><li>The <b>percent</b> parameter is the percent of the operation that has 58been completed, specified as an integer value between 0 and 100.</ul> 59<br></ul> 60<p>Berkeley DB is not re-entrant. Callback functions should not attempt to make 61library calls (for example, to release locks or close open handles). 62Re-entering Berkeley DB is not guaranteed to work correctly, and the results 63are undefined.</p> 64<br> 65<hr size=1 noshade> 66<br><b>Class</b> 67<a href="../api_c/env_class.html">DB_ENV</a> 68<br><b>See Also</b> 69<a href="../api_c/env_list.html">Database Environments and Related Methods</a> 70</tt> 71<table width="100%"><tr><td><br></td><td align=right> 72<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> 73</td></tr></table> 74<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 75</body> 76</html> 77
