devdocs/c/language%2Fstatic_storage_duration.html


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    <h1 id="firstHeading" class="firstHeading">Static storage duration</h1>            <p>An object whose identifier is declared without the storage-class specifier <code>_Thread_local</code>, and either with external or internal <a href="storage_duration#Linkage" title="c/language/storage duration">linkage</a> or with the storage-class specifier <code>static</code>, has static storage duration. Its lifetime is the entire execution of the program and its stored value is initialized only once, prior to program startup.</p>
<h3 id="Notes"> Notes</h3> <p>Since its stored value is initialized only once, an object with static storage duration can profile the invocations of a function.</p>
<p>The other use of the keyword <code>static</code> is <a href="file_scope" title="c/language/file scope">file scope</a>.</p>
<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include &lt;stdio.h&gt;
 
void f (void)
{
    static int count = 0;   // static variable   
    int i = 0;              // automatic variable
    printf("%d %d\n", i++, count++);
}
 
int main(void)
{
    for (int ndx=0; ndx&lt;10; ++ndx)
        f();
}</pre></div> <p>Output:</p>
<div class="text source-text"><pre data-language="c">0 0
0 1
0 2
0 3
0 4
0 5
0 6
0 7
0 8
0 9</pre></div> </div>           <div class="_attribution">
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