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<pre class="programlisting">#include <db.h>
int
db_env_set_func_yield(int (*func_yield)(u_long secs, u_long usecs)); </pre>
<p>
The Berkeley DB library requires the ability to yield the processor
from the current thread of control to any other waiting threads of
control.
</p>
<p>
The <span class="bold"><strong>func_yield</strong></span> function must be able
to cause the rescheduling of all participants in the current Berkeley
DB environment, whether threaded or not. It may be incorrect to
supply a thread <span class="bold"><strong>yield</strong></span> function if
more than a single process is operating in the Berkeley DB
environment. This is because many thread-yield functions will not
allow other processes to run, and the contested lock may be held by
another process, not by another thread.
</p>
<p>
The <code class="function">db_env_set_func_yield()</code> function configures all operations performed
by a process and all of its threads of control, not operations
confined to a single database environment.
</p>
<p>
Although the <code class="function">db_env_set_func_yield()</code> function may be called at any time
during the life of the application, it should normally be called
before making calls to the <a class="xref" href="envcreate.html" title="db_env_create">db_env_create</a> or
<a class="xref" href="dbcreate.html" title="db_create">db_create</a> methods.
</p>
<p>
The <code class="function">db_env_set_func_yield()</code> <span>
function returns a non-zero error value on failure and 0 on success.
</span>
</p>
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<h3 class="title"><a id="id1721496"></a>Parameters</h3>
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<h4 class="title"><a id="id1721389"></a>func_yield</h4>
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<p>
The <span class="bold"><strong>func_yield</strong></span> parameter is the
function which yields the processor.
</p>
<p>
The <span class="bold"><strong>secs</strong></span> parameter is the number of
seconds to pause before the thread of control should run again, or 0.
</p>
<p>
The <span class="bold"><strong>usecs</strong></span> parameter is the number of
microseconds to pause before the thread of control should run again,
or 0.
</p>
<p>
The <span class="bold"><strong>func_yield</strong></span> function must return
the value of <span class="bold"><strong>errno</strong></span> on failure and 0
on success.
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<h3 class="title"><a id="id1721642"></a>See Also</h3>
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<a href="../../programmer_reference/program_runtime.html" class="olink">Run-time configuration</a>
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