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DB_ENV-&gt;set_lk_detect
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<pre>
#include &lt;db.h&gt;

int
DB_ENV-&gt;set_lk_detect(DB_ENV *dbenv, u_int32_t detect);

int
DB_ENV-&gt;get_lk_detect(DB_ENV *dbenv, u_int32_t *lk_detectp);
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Description: DB_ENV-&gt;set_lk_detect
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.
The database environment's deadlock detector configuration may also be configured using the
environment's <a href="../../db4-devel-4.7.25/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_detect", one or more whitespace
characters, and the method detect parameter as a string; for example,
"set_lk_detect DB_LOCK_OLDEST".
Because the <a href="../../db4-devel-4.7.25/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.
The DB_ENV-&gt;set_lk_detect method configures a database environment, not only operations
performed using the specified <a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a> handle.
The DB_ENV-&gt;set_lk_detect method may be called at any time during the life of the
application.
The DB_ENV-&gt;set_lk_detect method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 detect<ul compact><li>The detect parameter configures the deadlock detector. The
specified value must be one of the following list:
 
<a name="DB_LOCK_DEFAULT">DB_LOCK_DEFAULT</a><ul compact><li>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.</ul>
<a name="DB_LOCK_EXPIRE">DB_LOCK_EXPIRE</a><ul compact><li>Reject lock requests which have timed out. No other deadlock detection
is performed.</ul>
<a name="DB_LOCK_MAXLOCKS">DB_LOCK_MAXLOCKS</a><ul compact><li>Reject the lock request for the locker ID with the most locks.</ul>
<a name="DB_LOCK_MAXWRITE">DB_LOCK_MAXWRITE</a><ul compact><li>Reject the lock request for the locker ID with the most write locks.</ul>
<a name="DB_LOCK_MINLOCKS">DB_LOCK_MINLOCKS</a><ul compact><li>Reject the lock request for the locker ID with the fewest locks.</ul>
<a name="DB_LOCK_MINWRITE">DB_LOCK_MINWRITE</a><ul compact><li>Reject the lock request for the locker ID with the fewest write locks.</ul>
<a name="DB_LOCK_OLDEST">DB_LOCK_OLDEST</a><ul compact><li>Reject the lock request for the locker ID with the oldest lock.</ul>
<a name="DB_LOCK_RANDOM">DB_LOCK_RANDOM</a><ul compact><li>Reject the lock request for a random locker ID.</ul>
<a name="DB_LOCK_YOUNGEST">DB_LOCK_YOUNGEST</a><ul compact><li>Reject the lock request for the locker ID with the youngest lock.</ul>
 </ul>
 
 Errors
The DB_ENV-&gt;set_lk_detect method
may fail and return one of the following non-zero errors:
 
EINVAL<ul compact><li>An
invalid flag value or parameter was specified.</ul>
 
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Description: DB_ENV-&gt;get_lk_detect
The DB_ENV-&gt;get_lk_detect method returns the deadlock detector configuration.
The DB_ENV-&gt;get_lk_detect method may be called at any time during the life of the
application.
The DB_ENV-&gt;get_lk_detect method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 lk_detectp<ul compact><li>The DB_ENV-&gt;get_lk_detect method returns the
deadlock detector configuration in lk_detectp.</ul>
 
<hr size=1 noshade>
 Class
<a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a>, <a href="../../db4-devel-4.7.25/api_c/lock_class.html">DB_LOCK</a>
 See Also
<a href="../../db4-devel-4.7.25/api_c/lock_list.html">Locking Subsystem and Related Methods</a>
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