<!--$Id: env_set_lk_detect.so,v 10.44 2003/11/08 19:17:31 bostic Exp $--> <!--Copyright 1997-2003 by Sleepycat Software, Inc.--> <!--All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: DB_ENV->set_lk_detect</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> <a name="2"><!--meow--></a> <table width="100%"><tr valign=top> <td> <h3>DB_ENV->set_lk_detect</h3> </td> <td align=right> <a href="../../db42-devel-4.2.52/api_c/api_index.html"><img src="../../db42-4.2.52/images/api.gif" alt="API"></a> <a href="../../db42-devel-4.2.52/ref/toc.html"><img src="../../db42-4.2.52/images/ref.gif" alt="Ref"></a> </td></tr></table> <hr size=1 noshade> <tt> <h3><pre> #include <db.h> <p> int DB_ENV->set_lk_detect(DB_ENV *dbenv, u_int32_t detect); <p> int DB_ENV->get_lk_detect(DB_ENV *dbenv, u_int32_t *lk_detectp); </pre></h3> <hr size=1 noshade> <h3>Description: DB_ENV->set_lk_detect</h3> <a name="3"><!--meow--></a> <p>Set if the deadlock detector is to be run whenever a lock conflict occurs, and specify what lock request(s) should be rejected. As transactions acquire locks on behalf of a single locker ID, rejecting a lock request associated with a transaction normally requires the transaction be aborted.</p> <p>The database environment's deadlock detector configuration may also be set using the environment's <b>DB_CONFIG</b> file. The syntax of the entry in that file is a single line with the string "set_lk_detect", one or more whitespace characters, and the method <b>detect</b> parameter as a string; for example, "set_lk_detect DB_LOCK_OLDEST". Because the <b>DB_CONFIG</b> file is read when the database environment is opened, it will silently overrule configuration done before that time.</p> <p>The DB_ENV->set_lk_detect method configures a database environment, not only operations performed using the specified <a href="../../db42-devel-4.2.52/api_c/env_class.html">DB_ENV</a> handle.</p> <p>The DB_ENV->set_lk_detect method may not be called after the <a href="../../db42-devel-4.2.52/api_c/env_open.html">DB_ENV->open</a> method is called. If the database environment already exists when <a href="../../db42-devel-4.2.52/api_c/env_open.html">DB_ENV->open</a> is called, the information specified to DB_ENV->set_lk_detect must be consistent with the existing environment or an error will be returned. </p> <p>The DB_ENV->set_lk_detect method returns a non-zero error value on failure and 0 on success. </p> <h3>Parameters</h3> <p><dl compact> <p><dt><b>detect</b><dd> The <b>detect</b> parameter configures the deadlock detector. The specified value must be one of the following list: <p><dl compact> <p><dt><a name="DB_LOCK_DEFAULT">DB_LOCK_DEFAULT</a><dd>Use whatever lock policy was specified when the database environment was created. If no lock policy has yet been specified, set the lock policy to DB_LOCK_RANDOM. <dt><a name="DB_LOCK_EXPIRE">DB_LOCK_EXPIRE</a><dd>Reject lock requests which have timed out. No other deadlock detection is performed. <dt><a name="DB_LOCK_MAXLOCKS">DB_LOCK_MAXLOCKS</a><dd>Reject the lock request for the locker ID with the greatest number of locks. <dt><a name="DB_LOCK_MINLOCKS">DB_LOCK_MINLOCKS</a><dd>Reject the lock request for the locker ID with the fewest number of locks. <dt><a name="DB_LOCK_MINWRITE">DB_LOCK_MINWRITE</a><dd>Reject the lock request for the locker ID with the fewest number of write locks. <dt><a name="DB_LOCK_OLDEST">DB_LOCK_OLDEST</a><dd>Reject the lock request for the oldest locker ID. <dt><a name="DB_LOCK_RANDOM">DB_LOCK_RANDOM</a><dd>Reject the lock request for a random locker ID. <dt><a name="DB_LOCK_YOUNGEST">DB_LOCK_YOUNGEST</a><dd>Reject the lock request for the youngest locker ID. </dl> </dl> <h3>Errors</h3> <p>The DB_ENV->set_lk_detect method may fail and return one of the following non-zero errors:</p> <p><dl compact> <p><dt>EINVAL<dd>If the method was called after <a href="../../db42-devel-4.2.52/api_c/env_open.html">DB_ENV->open</a> was called; or if an invalid flag value or parameter was specified. </dl> <hr size=1 noshade> <h3>Description: DB_ENV->get_lk_detect</h3> <p>The DB_ENV->get_lk_detect method returns the deadlock detector configuration.</p> <p>The DB_ENV->get_lk_detect method may be called at any time during the life of the application.</p> <p>The DB_ENV->get_lk_detect method returns a non-zero error value on failure and 0 on success. </p> <h3>Parameters</h3> <p><dl compact> <p><dt><b>lk_detectp</b><dd> The DB_ENV->get_lk_detect method returns the deadlock detector configuration in <b>lk_detectp</b>. </dl> <hr size=1 noshade> <h3>Class</h3> <a href="../../db42-devel-4.2.52/api_c/env_class.html">DB_ENV</a>, <a href="../../db42-devel-4.2.52/api_c/lock_class.html">DB_LOCK</a> <h3>See Also</h3> <a href="../../db42-devel-4.2.52/api_c/lock_list.html">Locking Subsystem and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <a href="../../db42-devel-4.2.52/api_c/api_index.html"><img src="../../db42-4.2.52/images/api.gif" alt="API"></a><a href="../../db42-devel-4.2.52/ref/toc.html"><img src="../../db42-4.2.52/images/ref.gif" alt="Ref"></a> </td></tr></table> <p><font size=1><a href="../../db42-devel-4.2.52/sleepycat/legal.html">Copyright (c) 1996-2003</a> <a href="http://www.sleepycat.com">Sleepycat Software, Inc.</a> - All rights reserved.</font> </body> </html>
distrib
>
Mandriva
>
2007.0
>
x86_64
>
media
>
main-release
>
by-pkgid
>
a4c98df40e78f6c892308fd6841f950a
>
files
>
104
