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diff --git a/devdocs/c/atomic%2Fatomic_fetch_or.html b/devdocs/c/atomic%2Fatomic_fetch_or.html new file mode 100644 index 00000000..5479688c --- /dev/null +++ b/devdocs/c/atomic%2Fatomic_fetch_or.html @@ -0,0 +1,26 @@ + <h1 id="firstHeading" class="firstHeading">atomic_fetch_or, atomic_fetch_or_explicit</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><stdatomic.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c11"> <td> <pre data-language="c">C atomic_fetch_or( volatile A* obj, M arg );</pre> +</td> <td> (1) </td> <td> <span class="t-mark-rev t-since-c11">(since C11)</span> </td> </tr> <tr class="t-dcl t-since-c11"> <td> <pre data-language="c">C atomic_fetch_or_explicit( volatile A* obj, M arg, memory_order order );</pre> +</td> <td> (2) </td> <td> <span class="t-mark-rev t-since-c11">(since C11)</span> </td> </tr> </table> <p>Atomically replaces the value pointed by <code>obj</code> with the result of bitwise OR between the old value of <code>obj</code> and <code>arg</code>, and returns the value <code>obj</code> held previously. The operation is read-modify-write operation. The first version orders memory accesses according to <code><a href="memory_order" title="c/atomic/memory order">memory_order_seq_cst</a></code>, the second version orders memory accesses according to <code>order</code>.</p> +<p>This is a <a href="../language/generic" title="c/language/generic">generic function</a> defined for all <a href="../language/atomic" title="c/language/atomic">atomic object types</a> <code>A</code>. The argument is pointer to a volatile atomic type to accept addresses of both non-volatile and <a href="../language/volatile" title="c/language/volatile">volatile</a> (e.g. memory-mapped I/O) atomic objects, and volatile semantic is preserved when applying this operation to volatile atomic objects. <code>M</code> is either the non-atomic type corresponding to <code>A</code> if <code>A</code> is atomic integer type, or <code><a href="../types/ptrdiff_t" title="c/types/ptrdiff t">ptrdiff_t</a></code> if <code>A</code> is atomic pointer type.</p> +<p>It is unspecified whether the name of a generic function is a macro or an identifier declared with external linkage. If a macro definition is suppressed in order to access an actual function (e.g. parenthesized like <code>(atomic_fetch_or)(...)</code>), or a program defines an external identifier with the name of a generic function, the behavior is undefined.</p> +<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> obj </td> <td> - </td> <td> pointer to the atomic object to modify </td> +</tr> <tr class="t-par"> <td> arg </td> <td> - </td> <td> the value to bitwise OR to the value stored in the atomic object </td> +</tr> <tr class="t-par"> <td> order </td> <td> - </td> <td> the memory synchronization ordering for this operation: all values are permitted </td> +</tr> +</table> <h3 id="Return_value"> Return value</h3> <p>The value held previously be the atomic object pointed to by <code>obj</code>.</p> +<h3 id="References"> References</h3> <ul> +<li> C17 standard (ISO/IEC 9899:2018): </li> +<ul><li> 7.17.7.5 The atomic_fetch and modify generic functions (p: 208) </li></ul> +<li> C11 standard (ISO/IEC 9899:2011): </li> +<ul><li> 7.17.7.5 The atomic_fetch and modify generic functions (p: 284-285) </li></ul> +</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="atomic_fetch_and" title="c/atomic/atomic fetch and"> <span class="t-lines"><span>atomic_fetch_and</span><span>atomic_fetch_and_explicit</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> atomic bitwise AND <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="atomic_fetch_xor" title="c/atomic/atomic fetch xor"> <span class="t-lines"><span>atomic_fetch_xor</span><span>atomic_fetch_xor_explicit</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> atomic bitwise exclusive OR <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/atomic/atomic_fetch_or" title="cpp/atomic/atomic fetch or">C++ documentation</a></span> for <code>atomic_fetch_or, atomic_fetch_or_explicit</code> </td> +</tr> </table> <div class="_attribution"> + <p class="_attribution-p"> + © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> + <a href="https://en.cppreference.com/w/c/atomic/atomic_fetch_or" class="_attribution-link">https://en.cppreference.com/w/c/atomic/atomic_fetch_or</a> + </p> +</div> |