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<b>DbEnv::set_lk_max_locks</b>
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<b><pre>
#include <db_cxx.h>
<p>
int
DbEnv::set_lk_max_locks(u_int32_t max);
<p>
int
DbEnv::get_lk_max_locks(u_int32_t *lk_maxp);
</pre></b>
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<b>Description: DbEnv::set_lk_max_locks</b>
<p>Set the maximum number of locks supported by the Berkeley DB environment.
This value is used by <a href="../api_cxx/env_open.html">DbEnv::open</a> to estimate how much space to
allocate for various lock-table data structures. The default value is
1000 locks. For specific information on configuring the size of the lock
subsystem, see <a href="../ref/lock/max.html">Configuring locking:
sizing the system</a>.</p>
<p>The database environment's maximum number of locks may also be configured using the
environment's <a href="../ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file. The syntax of the entry in that
file is a single line with the string "set_lk_max_locks", one or more whitespace
characters, and the number of locks.
Because the <a href="../ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file is read when the database environment
is opened, it will silently overrule configuration done before that
time.</p>
<p>The DbEnv::set_lk_max_locks method configures a database environment, not only operations
performed using the specified <a href="../api_cxx/env_class.html">DbEnv</a> handle.</p>
<p>The DbEnv::set_lk_max_locks method may not be called after the <a href="../api_cxx/env_open.html">DbEnv::open</a> method is
called.
If the database environment already exists when
<a href="../api_cxx/env_open.html">DbEnv::open</a> is called, the information specified to DbEnv::set_lk_max_locks
will be ignored.
</p>
<p>The DbEnv::set_lk_max_locks method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
<b>max</b><ul compact><li>The <b>max</b> parameter is the maximum number of locks supported by
the Berkeley DB environment.</ul>
<br>
<br><b>Errors</b>
<p>The DbEnv::set_lk_max_locks method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If the method was called after <a href="../api_cxx/env_open.html">DbEnv::open</a> was called; or if an
invalid flag value or parameter was specified.</ul>
<br>
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<b>Description: DbEnv::get_lk_max_locks</b>
<p>The DbEnv::get_lk_max_locks method returns the maximum number of locks.</p>
<p>The DbEnv::get_lk_max_locks method may be called at any time during the life of the
application.</p>
<p>The DbEnv::get_lk_max_locks method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
<b>lk_maxp</b><ul compact><li>The DbEnv::get_lk_max_locks method returns the
maximum number of locks in <b>lk_maxp</b>.</ul>
<br>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/lock_class.html">DbLock</a>
<br><b>See Also</b>
<a href="../api_cxx/lock_list.html">Locking Subsystem and Related Methods</a>
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