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| <a href="#" class="shortcut">Top</a><span id="nav_description"> <span class="dim">|</span> |
| <a href="#glib-Quarks.description" class="shortcut">Description</a></span> |
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| <div class="refentry"> |
| <a name="glib-Quarks"></a><div class="titlepage"></div> |
| <div class="refnamediv"><table width="100%"><tr> |
| <td valign="top"> |
| <h2><span class="refentrytitle"><a name="glib-Quarks.top_of_page"></a>Quarks</span></h2> |
| <p>Quarks — a 2-way association between a string and a |
| unique integer identifier</p> |
| </td> |
| <td class="gallery_image" valign="top" align="right"></td> |
| </tr></table></div> |
| <div class="refsect1"> |
| <a name="glib-Quarks.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="define_keyword">#define</td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#G-DEFINE-QUARK:CAPS" title="G_DEFINE_QUARK()">G_DEFINE_QUARK</a><span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="returnvalue">GQuark</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#g-quark-from-string" title="g_quark_from_string ()">g_quark_from_string</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="returnvalue">GQuark</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#g-quark-from-static-string" title="g_quark_from_static_string ()">g_quark_from_static_string</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> * |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#g-quark-to-string" title="g_quark_to_string ()">g_quark_to_string</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type"> |
| <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="returnvalue">GQuark</span></a> |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#g-quark-try-string" title="g_quark_try_string ()">g_quark_try_string</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> * |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#g-intern-string" title="g_intern_string ()">g_intern_string</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| <tr> |
| <td class="function_type">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> * |
| </td> |
| <td class="function_name"> |
| <a class="link" href="glib-Quarks.html#g-intern-static-string" title="g_intern_static_string ()">g_intern_static_string</a> <span class="c_punctuation">()</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Quarks.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="typedef_keyword">typedef</td> |
| <td class="function_name"><a class="link" href="glib-Quarks.html#GQuark" title="GQuark">GQuark</a></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Quarks.includes"></a><h2>Includes</h2> |
| <pre class="synopsis">#include <glib.h> |
| </pre> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Quarks.description"></a><h2>Description</h2> |
| <p>Quarks are associations between strings and integer identifiers. |
| Given either the string or the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> identifier it is possible to |
| retrieve the other.</p> |
| <p>Quarks are used for both <a class="link" href="glib-Datasets.html" title="Datasets">datasets</a> and |
| <a class="link" href="glib-Keyed-Data-Lists.html" title="Keyed Data Lists">keyed data lists</a>.</p> |
| <p>To create a new quark from a string, use <a class="link" href="glib-Quarks.html#g-quark-from-string" title="g_quark_from_string ()"><code class="function">g_quark_from_string()</code></a> or |
| <a class="link" href="glib-Quarks.html#g-quark-from-static-string" title="g_quark_from_static_string ()"><code class="function">g_quark_from_static_string()</code></a>.</p> |
| <p>To find the string corresponding to a given <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a>, use |
| <a class="link" href="glib-Quarks.html#g-quark-to-string" title="g_quark_to_string ()"><code class="function">g_quark_to_string()</code></a>.</p> |
| <p>To find the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> corresponding to a given string, use |
| <a class="link" href="glib-Quarks.html#g-quark-try-string" title="g_quark_try_string ()"><code class="function">g_quark_try_string()</code></a>.</p> |
| <p>Another use for the string pool maintained for the quark functions |
| is string interning, using <a class="link" href="glib-Quarks.html#g-intern-string" title="g_intern_string ()"><code class="function">g_intern_string()</code></a> or |
| <a class="link" href="glib-Quarks.html#g-intern-static-string" title="g_intern_static_string ()"><code class="function">g_intern_static_string()</code></a>. An interned string is a canonical |
| representation for a string. One important advantage of interned |
| strings is that they can be compared for equality by a simple |
| pointer comparison, rather than using <code class="function">strcmp()</code>.</p> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Quarks.functions_details"></a><h2>Functions</h2> |
| <div class="refsect2"> |
| <a name="G-DEFINE-QUARK:CAPS"></a><h3>G_DEFINE_QUARK()</h3> |
| <pre class="programlisting">#define G_DEFINE_QUARK(QN, q_n)</pre> |
| <p>A convenience macro which defines a function returning the |
| <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> for the name <em class="parameter"><code>QN</code></em> |
| . The function will be named |
| <em class="parameter"><code><code class="function">q_n_quark()</code></code></em> |
| .</p> |
| <p>Note that the quark name will be stringified automatically |
| in the macro, so you shouldn't use double quotes.</p> |
| <div class="refsect3"> |
| <a name="G-DEFINE-QUARK.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>QN</p></td> |
| <td class="parameter_description"><p>the name to return a <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> for</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| <tr> |
| <td class="parameter_name"><p>q_n</p></td> |
| <td class="parameter_description"><p>prefix for the function name</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-34.html#api-index-2.34">2.34</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-quark-from-string"></a><h3>g_quark_from_string ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="returnvalue">GQuark</span></a> |
| g_quark_from_string (<em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="type">gchar</span></a> *string</code></em>);</pre> |
| <p>Gets the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> identifying the given string. If the string does |
| not currently have an associated <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a>, a new <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> is created, |
| using a copy of the string.</p> |
| <div class="refsect3"> |
| <a name="g-quark-from-string.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>string</p></td> |
| <td class="parameter_description"><p> a string. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-quark-from-string.returns"></a><h4>Returns</h4> |
| <p> the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> identifying the string, or 0 if <em class="parameter"><code>string</code></em> |
| is <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a></p> |
| </div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-quark-from-static-string"></a><h3>g_quark_from_static_string ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="returnvalue">GQuark</span></a> |
| g_quark_from_static_string (<em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="type">gchar</span></a> *string</code></em>);</pre> |
| <p>Gets the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> identifying the given (static) string. If the |
| string does not currently have an associated <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a>, a new <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> |
| is created, linked to the given string.</p> |
| <p>Note that this function is identical to <a class="link" href="glib-Quarks.html#g-quark-from-string" title="g_quark_from_string ()"><code class="function">g_quark_from_string()</code></a> except |
| that if a new <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> is created the string itself is used rather |
| than a copy. This saves memory, but can only be used if the string |
| will continue to exist until the program terminates. It can be used |
| with statically allocated strings in the main program, but not with |
| statically allocated memory in dynamically loaded modules, if you |
| expect to ever unload the module again (e.g. do not use this |
| function in GTK+ theme engines).</p> |
| <div class="refsect3"> |
| <a name="g-quark-from-static-string.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>string</p></td> |
| <td class="parameter_description"><p> a string. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-quark-from-static-string.returns"></a><h4>Returns</h4> |
| <p> the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> identifying the string, or 0 if <em class="parameter"><code>string</code></em> |
| is <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a></p> |
| </div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-quark-to-string"></a><h3>g_quark_to_string ()</h3> |
| <pre class="programlisting">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> * |
| g_quark_to_string (<em class="parameter"><code><a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> quark</code></em>);</pre> |
| <p>Gets the string associated with the given <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a>.</p> |
| <div class="refsect3"> |
| <a name="g-quark-to-string.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>quark</p></td> |
| <td class="parameter_description"><p>a <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a>.</p></td> |
| <td class="parameter_annotations"> </td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-quark-to-string.returns"></a><h4>Returns</h4> |
| <p> the string associated with the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a></p> |
| </div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-quark-try-string"></a><h3>g_quark_try_string ()</h3> |
| <pre class="programlisting"><a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="returnvalue">GQuark</span></a> |
| g_quark_try_string (<em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="type">gchar</span></a> *string</code></em>);</pre> |
| <p>Gets the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> associated with the given string, or 0 if string is |
| <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a> or it has no associated <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a>.</p> |
| <p>If you want the GQuark to be created if it doesn't already exist, |
| use <a class="link" href="glib-Quarks.html#g-quark-from-string" title="g_quark_from_string ()"><code class="function">g_quark_from_string()</code></a> or <a class="link" href="glib-Quarks.html#g-quark-from-static-string" title="g_quark_from_static_string ()"><code class="function">g_quark_from_static_string()</code></a>.</p> |
| <div class="refsect3"> |
| <a name="g-quark-try-string.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>string</p></td> |
| <td class="parameter_description"><p> a string. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-quark-try-string.returns"></a><h4>Returns</h4> |
| <p> the <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> associated with the string, or 0 if <em class="parameter"><code>string</code></em> |
| is |
| <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a> or there is no <a class="link" href="glib-Quarks.html#GQuark" title="GQuark"><span class="type">GQuark</span></a> associated with it</p> |
| </div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-intern-string"></a><h3>g_intern_string ()</h3> |
| <pre class="programlisting">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> * |
| g_intern_string (<em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="type">gchar</span></a> *string</code></em>);</pre> |
| <p>Returns a canonical representation for <em class="parameter"><code>string</code></em> |
| . Interned strings |
| can be compared for equality by comparing the pointers, instead of |
| using <code class="function">strcmp()</code>.</p> |
| <div class="refsect3"> |
| <a name="g-intern-string.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>string</p></td> |
| <td class="parameter_description"><p> a string. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-intern-string.returns"></a><h4>Returns</h4> |
| <p> a canonical representation for the string</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-10.html#api-index-2.10">2.10</a></p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="g-intern-static-string"></a><h3>g_intern_static_string ()</h3> |
| <pre class="programlisting">const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="returnvalue">gchar</span></a> * |
| g_intern_static_string (<em class="parameter"><code>const <a class="link" href="glib-Basic-Types.html#gchar" title="gchar"><span class="type">gchar</span></a> *string</code></em>);</pre> |
| <p>Returns a canonical representation for <em class="parameter"><code>string</code></em> |
| . Interned strings |
| can be compared for equality by comparing the pointers, instead of |
| using <code class="function">strcmp()</code>. <a class="link" href="glib-Quarks.html#g-intern-static-string" title="g_intern_static_string ()"><code class="function">g_intern_static_string()</code></a> does not copy the string, |
| therefore <em class="parameter"><code>string</code></em> |
| must not be freed or modified.</p> |
| <div class="refsect3"> |
| <a name="g-intern-static-string.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>string</p></td> |
| <td class="parameter_description"><p> a static string. </p></td> |
| <td class="parameter_annotations"><span class="annotation">[<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect3"> |
| <a name="g-intern-static-string.returns"></a><h4>Returns</h4> |
| <p> a canonical representation for the string</p> |
| </div> |
| <p class="since">Since: <a class="link" href="api-index-2-10.html#api-index-2.10">2.10</a></p> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="glib-Quarks.other_details"></a><h2>Types and Values</h2> |
| <div class="refsect2"> |
| <a name="GQuark"></a><h3>GQuark</h3> |
| <pre class="programlisting">typedef guint32 GQuark; |
| </pre> |
| <p>A GQuark is a non-zero integer which uniquely identifies a |
| particular string. A GQuark value of zero is associated to <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a>.</p> |
| </div> |
| </div> |
| </div> |
| <div class="footer"> |
| <hr>Generated by GTK-Doc V1.25.1</div> |
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