devdocs/c/thread%2Ftss_set.html


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    <h1 id="firstHeading" class="firstHeading">tss_set</h1>            <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code>&lt;threads.h&gt;</code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c11"> <td> <pre data-language="c">int tss_set( tss_t tss_id, void *val );</pre>
</td> <td class="t-dcl-nopad"> </td> <td> <span class="t-mark-rev t-since-c11">(since C11)</span> </td> </tr>  </table> <p>Sets the value of the thread-specific storage identified by <code>tss_id</code> for the current thread to <code>val</code>. Different threads may set different values to the same key.</p>
<p>The destructor, if available, is not invoked.</p>
<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> tss_id </td> <td> - </td> <td> thread-specific storage key, obtained from <code><a href="tss_create" title="c/thread/tss create">tss_create</a></code> and not deleted by <code><a href="tss_delete" title="c/thread/tss delete">tss_delete</a></code> </td>
</tr> <tr class="t-par"> <td> val </td> <td> - </td> <td> value to set thread-specific storage to </td>
</tr>
</table> <h3 id="Return_value"> Return value</h3> <p><code><a href="thrd_errors" title="c/thread/thrd errors">thrd_success</a></code> if successful, <code><a href="thrd_errors" title="c/thread/thrd errors">thrd_error</a></code> otherwise.</p>
<h3 id="Notes"> Notes</h3> <p>The POSIX equivalent of this function is <a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_setspecific.html"><code>pthread_setspecific</code></a>.</p>
<p>Typically TSS is used to store pointers to blocks of dynamically allocated memory that have been reserved for use by the calling thread.</p>
<p><code>tss_set</code> may be called in the TSS destructor. If the destructor exits with non-NULL value in the TSS storage, it will be retried by <code><a href="thrd_exit" title="c/thread/thrd exit">thrd_exit</a></code> up to <code><a href="tss_dtor_iterations" title="c/thread/TSS DTOR ITERATIONS">TSS_DTOR_ITERATIONS</a></code> times, after which the storage will be lost.</p>
<h3 id="Example"> Example</h3>  <div class="c source-c"><pre data-language="c">int thread_func(void *arg) {
    tss_t key;
    if (thrd_success == tss_create(&amp;key, free)) {
        tss_set(key, malloc(4)); // stores a pointer on TSS
        // ...
    }
} // calls free() for the pointer stored on TSS</pre></div> <h3 id="References"> References</h3>  <ul>
<li> C17 standard (ISO/IEC 9899:2018): </li>
<ul><li> 7.26.6.4 The tss_set function (p: 282-283) </li></ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul><li> 7.26.6.4 The tss_set function (p: 387) </li></ul>
</ul>       <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="tss_get" title="c/thread/tss get"> <span class="t-lines"><span>tss_get</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div> </td> <td> reads from thread-specific storage <br> <span class="t-mark">(function)</span>  </td>
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