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| <a name="glib-Atomic-Operations"></a><div class="titlepage"></div> |
| <div class="refnamediv"><table width="100%"><tr> |
| <td valign="top"> |
| <h2><span class="refentrytitle"><a name="glib-Atomic-Operations.top_of_page"></a>Atomic Operations</span></h2> |
| <p>Atomic Operations — basic atomic integer and pointer operations</p> |
| </td> |
| <td class="gallery_image" valign="top" align="right"></td> |
| </tr></table></div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.functions"></a><h2>Functions</h2> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="functions_return"> |
| <col class="functions_name"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="returnvalue">gint</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-get" title="g_atomic_int_get ()">g_atomic_int_get</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <span class="returnvalue">void</span> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-set" title="g_atomic_int_set ()">g_atomic_int_set</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <span class="returnvalue">void</span> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-inc" title="g_atomic_int_inc ()">g_atomic_int_inc</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gboolean" title="gboolean"><span class="returnvalue">gboolean</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-dec-and-test" title="g_atomic_int_dec_and_test ()">g_atomic_int_dec_and_test</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gboolean" title="gboolean"><span class="returnvalue">gboolean</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-compare-and-exchange" title="g_atomic_int_compare_and_exchange ()">g_atomic_int_compare_and_exchange</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="returnvalue">gint</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-add" title="g_atomic_int_add ()">g_atomic_int_add</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="returnvalue">guint</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-and" title="g_atomic_int_and ()">g_atomic_int_and</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="returnvalue">guint</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-or" title="g_atomic_int_or ()">g_atomic_int_or</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="returnvalue">guint</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-xor" title="g_atomic_int_xor ()">g_atomic_int_xor</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gpointer" title="gpointer"><span class="returnvalue">gpointer</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-get" title="g_atomic_pointer_get ()">g_atomic_pointer_get</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <span class="returnvalue">void</span> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-set" title="g_atomic_pointer_set ()">g_atomic_pointer_set</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gboolean" title="gboolean"><span class="returnvalue">gboolean</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-compare-and-exchange" title="g_atomic_pointer_compare_and_exchange ()">g_atomic_pointer_compare_and_exchange</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="returnvalue">gssize</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-add" title="g_atomic_pointer_add ()">g_atomic_pointer_add</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="returnvalue">gsize</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-and" title="g_atomic_pointer_and ()">g_atomic_pointer_and</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="returnvalue">gsize</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-or" title="g_atomic_pointer_or ()">g_atomic_pointer_or</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="returnvalue">gsize</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-pointer-xor" title="g_atomic_pointer_xor ()">g_atomic_pointer_xor</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="returnvalue">gint</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-exchange-and-add" title="g_atomic_int_exchange_and_add ()">g_atomic_int_exchange_and_add</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.other"></a><h2>Types and Values</h2> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="name"> |
| <col class="description"> |
| </colgroup> |
| <tbody><tr> |
| <td class="define_keyword">#define</td> |
| <td class="function_name"><a class="link" href="glib-Atomic-Operations.html#G-ATOMIC-LOCK-FREE:CAPS" title="G_ATOMIC_LOCK_FREE">G_ATOMIC_LOCK_FREE</a></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.includes"></a><h2>Includes</h2> |
| <pre class="synopsis">#include <glib.h> |
| </pre> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.description"></a><h2>Description</h2> |
| <p>The following is a collection of compiler macros to provide atomic |
| access to integer and pointer-sized values.</p> |
| <p>The macros that have 'int' in the name will operate on pointers to |
| <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> and <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a>. The macros with 'pointer' in the name will operate |
| on pointers to any pointer-sized value, including <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a>. There is |
| no support for 64bit operations on platforms with 32bit pointers |
| because it is not generally possible to perform these operations |
| atomically.</p> |
| <p>The get, set and exchange operations for integers and pointers |
| nominally operate on <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> and <a class="link" href="glib-Basic-Types.html#gpointer" title="gpointer"><span class="type">gpointer</span></a>, respectively. Of the |
| arithmetic operations, the 'add' operation operates on (and returns) |
| signed integer values (<a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> and <a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="type">gssize</span></a>) and the 'and', 'or', and |
| 'xor' operations operate on (and return) unsigned integer values |
| (<a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> and <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a>).</p> |
| <p>All of the operations act as a full compiler and (where appropriate) |
| hardware memory barrier. Acquire and release or producer and |
| consumer barrier semantics are not available through this API.</p> |
| <p>It is very important that all accesses to a particular integer or |
| pointer be performed using only this API and that different sizes of |
| operation are not mixed or used on overlapping memory regions. Never |
| read or assign directly from or to a value -- always use this API.</p> |
| <p>For simple reference counting purposes you should use |
| <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-inc" title="g_atomic_int_inc ()"><code class="function">g_atomic_int_inc()</code></a> and <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-dec-and-test" title="g_atomic_int_dec_and_test ()"><code class="function">g_atomic_int_dec_and_test()</code></a>. Other uses that |
| fall outside of simple reference counting patterns are prone to |
| subtle bugs and occasionally undefined behaviour. It is also worth |
| noting that since all of these operations require global |
| synchronisation of the entire machine, they can be quite slow. In |
| the case of performing multiple atomic operations it can often be |
| faster to simply acquire a mutex lock around the critical area, |
| perform the operations normally and then release the lock.</p> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.functions_details"></a><h2>Functions</h2> |
| <div class="refsect2"> |
| <a name="g-atomic-int-get"></a><h3>g_atomic_int_get ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="returnvalue">gint</span></a> |
| g_atomic_int_get (<em class="parameter"><code>const volatile <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>);</pre> |
| <p>Gets the current value of <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>This call acts as a full compiler and hardware |
| memory barrier (before the get).</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-get.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody><tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-get.returns"></a><h4>Returns</h4> |
| <p> the value of the integer</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-set"></a><h3>g_atomic_int_set ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> |
| g_atomic_int_set (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> newval</code></em>);</pre> |
| <p>Sets the value of <em class="parameter"><code>atomic</code></em> |
| to <em class="parameter"><code>newval</code></em> |
| .</p> |
| <p>This call acts as a full compiler and hardware |
| memory barrier (after the set).</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-set.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>newval</p></td> |
| <td class="parameter_description"><p>a new value to store</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-inc"></a><h3>g_atomic_int_inc ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> |
| g_atomic_int_inc (<em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>);</pre> |
| <p>Increments the value of <em class="parameter"><code>atomic</code></em> |
| by 1.</p> |
| <p>Think of this operation as an atomic version of <code class="literal">{ *atomic += 1; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-inc.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody><tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-dec-and-test"></a><h3>g_atomic_int_dec_and_test ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gboolean" title="gboolean"><span class="returnvalue">gboolean</span></a> |
| g_atomic_int_dec_and_test (<em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>);</pre> |
| <p>Decrements the value of <em class="parameter"><code>atomic</code></em> |
| by 1.</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ *atomic -= 1; return (*atomic == 0); }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-dec-and-test.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody><tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-dec-and-test.returns"></a><h4>Returns</h4> |
| <p> <a class="link" href="glib-Standard-Macros.html#TRUE:CAPS" title="TRUE"><code class="literal">TRUE</code></a> if the resultant value is zero</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-compare-and-exchange"></a><h3>g_atomic_int_compare_and_exchange ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gboolean" title="gboolean"><span class="returnvalue">gboolean</span></a> |
| g_atomic_int_compare_and_exchange (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> oldval</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> newval</code></em>);</pre> |
| <p>Compares <em class="parameter"><code>atomic</code></em> |
| to <em class="parameter"><code>oldval</code></em> |
| and, if equal, sets it to <em class="parameter"><code>newval</code></em> |
| . |
| If <em class="parameter"><code>atomic</code></em> |
| was not equal to <em class="parameter"><code>oldval</code></em> |
| then no change occurs.</p> |
| <p>This compare and exchange is done atomically.</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ if (*atomic == oldval) { *atomic = newval; return TRUE; } else return FALSE; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-compare-and-exchange.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>oldval</p></td> |
| <td class="parameter_description"><p>the value to compare with</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>newval</p></td> |
| <td class="parameter_description"><p>the value to conditionally replace with</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-compare-and-exchange.returns"></a><h4>Returns</h4> |
| <p> <a class="link" href="glib-Standard-Macros.html#TRUE:CAPS" title="TRUE"><code class="literal">TRUE</code></a> if the exchange took place</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-add"></a><h3>g_atomic_int_add ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="returnvalue">gint</span></a> |
| g_atomic_int_add (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> val</code></em>);</pre> |
| <p>Atomically adds <em class="parameter"><code>val</code></em> |
| to the value of <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic += val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <p>Before version 2.30, this function did not return a value |
| (but <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-exchange-and-add" title="g_atomic_int_exchange_and_add ()"><code class="function">g_atomic_int_exchange_and_add()</code></a> did, and had the same meaning).</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-add.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to add</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-add.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the add, signed</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-and"></a><h3>g_atomic_int_and ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="returnvalue">guint</span></a> |
| g_atomic_int_and (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> val</code></em>);</pre> |
| <p>Performs an atomic bitwise 'and' of the value of <em class="parameter"><code>atomic</code></em> |
| and <em class="parameter"><code>val</code></em> |
| , |
| storing the result back in <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic &= val; return tmp; }</code>.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-and.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to 'and'</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-and.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the operation, unsigned</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-or"></a><h3>g_atomic_int_or ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="returnvalue">guint</span></a> |
| g_atomic_int_or (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> val</code></em>);</pre> |
| <p>Performs an atomic bitwise 'or' of the value of <em class="parameter"><code>atomic</code></em> |
| and <em class="parameter"><code>val</code></em> |
| , |
| storing the result back in <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic |= val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-or.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to 'or'</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-or.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the operation, unsigned</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-xor"></a><h3>g_atomic_int_xor ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="returnvalue">guint</span></a> |
| g_atomic_int_xor (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a> val</code></em>);</pre> |
| <p>Performs an atomic bitwise 'xor' of the value of <em class="parameter"><code>atomic</code></em> |
| and <em class="parameter"><code>val</code></em> |
| , |
| storing the result back in <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic ^= val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-xor.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> or <a class="link" href="glib-Basic-Types.html#guint" title="guint ()"><span class="type">guint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to 'xor'</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-xor.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the operation, unsigned</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-get"></a><h3>g_atomic_pointer_get ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gpointer" title="gpointer"><span class="returnvalue">gpointer</span></a> |
| g_atomic_pointer_get (<em class="parameter"><code>const volatile <span class="type">void</span> *atomic</code></em>);</pre> |
| <p>Gets the current value of <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>This call acts as a full compiler and hardware |
| memory barrier (before the get).</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-get.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody><tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-get.returns"></a><h4>Returns</h4> |
| <p> the value of the pointer</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-set"></a><h3>g_atomic_pointer_set ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> |
| g_atomic_pointer_set (<em class="parameter"><code>volatile <span class="type">void</span> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gpointer" title="gpointer"><span class="type">gpointer</span></a> newval</code></em>);</pre> |
| <p>Sets the value of <em class="parameter"><code>atomic</code></em> |
| to <em class="parameter"><code>newval</code></em> |
| .</p> |
| <p>This call acts as a full compiler and hardware |
| memory barrier (after the set).</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-set.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>newval</p></td> |
| <td class="parameter_description"><p>a new value to store</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-compare-and-exchange"></a><h3>g_atomic_pointer_compare_and_exchange ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gboolean" title="gboolean"><span class="returnvalue">gboolean</span></a> |
| g_atomic_pointer_compare_and_exchange (<em class="parameter"><code>volatile <span class="type">void</span> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gpointer" title="gpointer"><span class="type">gpointer</span></a> oldval</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gpointer" title="gpointer"><span class="type">gpointer</span></a> newval</code></em>);</pre> |
| <p>Compares <em class="parameter"><code>atomic</code></em> |
| to <em class="parameter"><code>oldval</code></em> |
| and, if equal, sets it to <em class="parameter"><code>newval</code></em> |
| . |
| If <em class="parameter"><code>atomic</code></em> |
| was not equal to <em class="parameter"><code>oldval</code></em> |
| then no change occurs.</p> |
| <p>This compare and exchange is done atomically.</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ if (*atomic == oldval) { *atomic = newval; return TRUE; } else return FALSE; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-compare-and-exchange.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>oldval</p></td> |
| <td class="parameter_description"><p>the value to compare with</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>newval</p></td> |
| <td class="parameter_description"><p>the value to conditionally replace with</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-compare-and-exchange.returns"></a><h4>Returns</h4> |
| <p> <a class="link" href="glib-Standard-Macros.html#TRUE:CAPS" title="TRUE"><code class="literal">TRUE</code></a> if the exchange took place</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-add"></a><h3>g_atomic_pointer_add ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="returnvalue">gssize</span></a> |
| g_atomic_pointer_add (<em class="parameter"><code>volatile <span class="type">void</span> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="type">gssize</span></a> val</code></em>);</pre> |
| <p>Atomically adds <em class="parameter"><code>val</code></em> |
| to the value of <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic += val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-add.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to add</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-add.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the add, signed</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-and"></a><h3>g_atomic_pointer_and ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="returnvalue">gsize</span></a> |
| g_atomic_pointer_and (<em class="parameter"><code>volatile <span class="type">void</span> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a> val</code></em>);</pre> |
| <p>Performs an atomic bitwise 'and' of the value of <em class="parameter"><code>atomic</code></em> |
| and <em class="parameter"><code>val</code></em> |
| , |
| storing the result back in <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic &= val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-and.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to 'and'</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-and.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the operation, unsigned</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-or"></a><h3>g_atomic_pointer_or ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="returnvalue">gsize</span></a> |
| g_atomic_pointer_or (<em class="parameter"><code>volatile <span class="type">void</span> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a> val</code></em>);</pre> |
| <p>Performs an atomic bitwise 'or' of the value of <em class="parameter"><code>atomic</code></em> |
| and <em class="parameter"><code>val</code></em> |
| , |
| storing the result back in <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic |= val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-or.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to 'or'</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-or.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the operation, unsigned</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-pointer-xor"></a><h3>g_atomic_pointer_xor ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="returnvalue">gsize</span></a> |
| g_atomic_pointer_xor (<em class="parameter"><code>volatile <span class="type">void</span> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a> val</code></em>);</pre> |
| <p>Performs an atomic bitwise 'xor' of the value of <em class="parameter"><code>atomic</code></em> |
| and <em class="parameter"><code>val</code></em> |
| , |
| storing the result back in <em class="parameter"><code>atomic</code></em> |
| .</p> |
| <p>Think of this operation as an atomic version of |
| <code class="literal">{ tmp = *atomic; *atomic ^= val; return tmp; }</code>.</p> |
| <p>This call acts as a full compiler and hardware memory barrier.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-xor.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p> a pointer to a <span class="type">gpointer-sized</span> value. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL must not be passed as the value in, out, in-out; or as a return value."><span class="acronym">not nullable</span></acronym>]</span></td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to 'xor'</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-pointer-xor.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the operation, unsigned</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-30.html#api-index-2.30">2.30</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-atomic-int-exchange-and-add"></a><h3>g_atomic_int_exchange_and_add ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="returnvalue">gint</span></a> |
| g_atomic_int_exchange_and_add (<em class="parameter"><code>volatile <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> *atomic</code></em>, |
| <em class="parameter"><code><a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a> val</code></em>);</pre> |
| <div class="warning"> |
| <p><code class="literal">g_atomic_int_exchange_and_add</code> has been deprecated since version 2.30 and should not be used in newly-written code.</p> |
| <p>Use <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-add" title="g_atomic_int_add ()"><code class="function">g_atomic_int_add()</code></a> instead.</p> |
| </div> |
| <p>This function existed before <a class="link" href="glib-Atomic-Operations.html#g-atomic-int-add" title="g_atomic_int_add ()"><code class="function">g_atomic_int_add()</code></a> returned the prior |
| value of the integer (which it now does). It is retained only for |
| compatibility reasons. Don't use this function in new code.</p> |
| <div class="refsect3"> |
| <a name="g-atomic-int-exchange-and-add.parameters"></a><h4>Parameters</h4> |
| <div class="informaltable"><table class="informaltable" width="100%" border="0"> |
| <colgroup> |
| <col width="150px" class="parameters_name"> |
| <col class="parameters_description"> |
| <col width="200px" class="parameters_annotations"> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td class="parameter_name"><p>atomic</p></td> |
| <td class="parameter_description"><p>a pointer to a <a class="link" href="glib-Basic-Types.html#gint" title="gint ()"><span class="type">gint</span></a></p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>val</p></td> |
| <td class="parameter_description"><p>the value to add</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-atomic-int-exchange-and-add.returns"></a><h4>Returns</h4> |
| <p> the value of <em class="parameter"><code>atomic</code></em> |
| before the add, signed</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-4.html#api-index-2.4">2.4</a></p> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.other_details"></a><h2>Types and Values</h2> |
| <div class="refsect2"> |
| <a name="G-ATOMIC-LOCK-FREE:CAPS"></a><h3>G_ATOMIC_LOCK_FREE</h3> |
| <pre class="programlisting">#define G_ATOMIC_LOCK_FREE |
| </pre> |
| <p>This macro is defined if the atomic operations of GLib are |
| implemented using real hardware atomic operations. This means that |
| the GLib atomic API can be used between processes and safely mixed |
| with other (hardware) atomic APIs.</p> |
| <p>If this macro is not defined, the atomic operations may be |
| emulated using a mutex. In that case, the GLib atomic operations are |
| only atomic relative to themselves and within a single process.</p> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Atomic-Operations.see-also"></a><h2>See Also</h2> |
| <p><a class="link" href="glib-Threads.html#GMutex" title="union GMutex"><span class="type">GMutex</span></a></p> |
| </div> |
| </div> |
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