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<a href="#nested-classes">Data Structures</a> |
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<div class="title">One-time execution<div class="ingroups"><a class="el" href="group__globus__thread.html">Threading</a></div></div> </div>
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Data Structures</h2></td></tr>
<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">union  </td><td class="memItemRight" valign="bottom"><a class="el" href="unionglobus__thread__once__t.html">globus_thread_once_t</a></td></tr>
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Macros</h2></td></tr>
<tr class="memitem:ga38b6477d7d8d53dcbbf6a6f8efc48128"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group__globus__thread__once.html#ga38b6477d7d8d53dcbbf6a6f8efc48128">GLOBUS_THREAD_ONCE_INIT</a>   { .none = 0 }</td></tr>
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Functions</h2></td></tr>
<tr class="memitem:gae997dbf80ee410d7762083c5e3967b27"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__globus__thread__once.html#gae997dbf80ee410d7762083c5e3967b27">globus_thread_once</a> (<a class="el" href="unionglobus__thread__once__t.html">globus_thread_once_t</a> *once, void(*init_routine)(void))</td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<p>The <a class="el" href="unionglobus__thread__once__t.html" title="Thread once structure.">globus_thread_once_t</a> provides a way for applications and libraries to execute some code exactly one time, independent of the number of threads which attempt to execute it. To use this, statically initialize a <a class="el" href="unionglobus__thread__once__t.html" title="Thread once structure.">globus_thread_once_t</a> control with the value GLOBUS_THREAD_ONCE_INIT, and pass a pointer to a function to execute once, along with the control, to <a class="el" href="group__globus__thread__once.html#gae997dbf80ee410d7762083c5e3967b27" title="Execute a function one time.">globus_thread_once()</a>. </p>
<h2 class="groupheader">Macro Definition Documentation</h2>
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<td class="memname">#define GLOBUS_THREAD_ONCE_INIT   { .none = 0 }</td>
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<p>Thread once initializer value. </p>
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<h2 class="groupheader">Function Documentation</h2>
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<td class="memname">int globus_thread_once </td>
<td>(</td>
<td class="paramtype"><a class="el" href="unionglobus__thread__once__t.html">globus_thread_once_t</a> * </td>
<td class="paramname"><em>once</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">void(*)(void) </td>
<td class="paramname"><em>init_routine</em> </td>
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<p>Execute a function one time. </p>
<pre class="fragment">The globus_thread_once() function will execute the function pointed to
by its @a init_routine parameter one time for each unique
globus_thread_once_t object passed to it, independent of the number
of threads calling it. The @a once value must be a static value
initialized to GLOBUS_THREAD_ONCE_INIT.
</pre><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">once</td><td>A pointer to the value used to govern whether the function passed via the <em>init_routine</em> parameter has executed. </td></tr>
<tr><td class="paramname">init_routine</td><td>Function to execute one time. It is called with no parameters.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>On success, <a class="el" href="group__globus__thread__once.html#gae997dbf80ee410d7762083c5e3967b27" title="Execute a function one time.">globus_thread_once()</a> guarantees that the function pointed to by <em>init_routine</em> has run, and that subsequent calls to <a class="el" href="group__globus__thread__once.html#gae997dbf80ee410d7762083c5e3967b27" title="Execute a function one time.">globus_thread_once()</a> with the same value of <em>once</em> will not execute that function, and returns GLOBUS_SUCCESS. If an error occurs, <a class="el" href="group__globus__thread__once.html#gae997dbf80ee410d7762083c5e3967b27" title="Execute a function one time.">globus_thread_once()</a> returns an implementation-specific non-zero error value. </dd></dl>
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