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

int
DB_ENV-&gt;mutex_set_tas_spins(DB_ENV *dbenv, u_int32_t tas_spins);

int
DB_ENV-&gt;mutex_get_tas_spins(DB_ENV *dbenv, u_int32_t *tas_spinsp);
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Description: DB_ENV-&gt;mutex_set_tas_spins
Specify that test-and-set mutexes should spin tas_spins times
without blocking. The value defaults to 1 on uniprocessor systems and
to 50 times the number of processors on multiprocessor systems.
The database environment's test-and-set spin count 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_tas_spins", one or more whitespace
characters, and the number of spins.
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;mutex_set_tas_spins method configures operations performed using the specified
<a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a> handle, not all operations performed on the underlying
database environment.
The DB_ENV-&gt;mutex_set_tas_spins method may be called at any time during the life of the
application.
The DB_ENV-&gt;mutex_set_tas_spins method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 tas_spins<ul compact><li>The tas_spins parameter is the number of spins test-and-set
mutexes should execute before blocking.</ul>
 
 Errors
The DB_ENV-&gt;mutex_set_tas_spins 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;mutex_get_tas_spins
The DB_ENV-&gt;mutex_get_tas_spins method returns the test-and-set spin count.
The DB_ENV-&gt;mutex_get_tas_spins method may be called at any time during the life of the
application.
The DB_ENV-&gt;mutex_get_tas_spins method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 tas_spinsp<ul compact><li>The DB_ENV-&gt;mutex_get_tas_spins method returns the
test-and-set spin count in tas_spinsp.</ul>
 
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 Class
<a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a>
 See Also
<a href="../../db4-devel-4.7.25/api_c/env_list.html">Database Environments and Related Methods</a>
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