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<h1>Hook Extension<br/>
<small>
[<a class="el" href="group___p_c_m.html">PCM Interface</a>]</small>
</h1><table border="0" cellpadding="0" cellspacing="0">
<tr><td colspan="2"><h2>Files</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">file </td><td class="memItemRight" valign="bottom"><a class="el" href="pcm__hooks_8c.html">pcm_hooks.c</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p>PCM Hook Interface. </p>
<br/></td></tr>
</p>
<tr><td colspan="2"><h2>Typedefs</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">typedef struct _snd_pcm_hook </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">typedef int(* </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#gaff0efa33d6ffbe1df2492ad0d30df309">snd_pcm_hook_func_t</a> )(<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> *hook)</td></tr>
<tr><td colspan="2"><h2>Enumerations</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">enum </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#ga57b6ba407d293017e116fa1b462a2411">snd_pcm_hook_type_t</a> { <b>SND_PCM_HOOK_TYPE_HW_PARAMS</b> = 0,
<b>SND_PCM_HOOK_TYPE_HW_FREE</b>,
<b>SND_PCM_HOOK_TYPE_CLOSE</b>,
<b>SND_PCM_HOOK_TYPE_LAST</b> = SND_PCM_HOOK_TYPE_CLOSE
}</td></tr>
<tr><td colspan="2"><h2>Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#gacaec88e4b6cc2a45e7a805487acd64ed">snd_pcm_hook_get_pcm</a> (<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> *hook)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get PCM handle for a PCM hook. <a href="#gacaec88e4b6cc2a45e7a805487acd64ed"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void * </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#ga1eb467cd5ab11817edc2ed7df3608019">snd_pcm_hook_get_private</a> (<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> *hook)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get callback function private data for a PCM hook. <a href="#ga1eb467cd5ab11817edc2ed7df3608019"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#ga6930df3b750b3f62dee6846fb3f6a576">snd_pcm_hook_set_private</a> (<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> *hook, void *private_data)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set callback function private data for a PCM hook. <a href="#ga6930df3b750b3f62dee6846fb3f6a576"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#ga89eed2fdcda68c1efae9180a3794d5ef">snd_pcm_hook_add</a> (<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> **hookp, <a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> *pcm, <a class="el" href="group___p_c_m___hook.html#ga57b6ba407d293017e116fa1b462a2411">snd_pcm_hook_type_t</a> type, <a class="el" href="group___p_c_m___hook.html#gaff0efa33d6ffbe1df2492ad0d30df309">snd_pcm_hook_func_t</a> func, void *private_data)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Add a PCM hook at end of hooks chain. <a href="#ga89eed2fdcda68c1efae9180a3794d5ef"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___p_c_m___hook.html#ga4c59ad440d2479f957b477b26b90e4b1">snd_pcm_hook_remove</a> (<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> *hook)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Remove a PCM hook. <a href="#ga4c59ad440d2479f957b477b26b90e4b1"></a><br/></td></tr>
</table>
<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>See the <a class="el" href="pcm.html">PCM (digital audio) interface</a> page for more details. </p>
<hr/><h2>Typedef Documentation</h2>
<a class="anchor" id="gaff0efa33d6ffbe1df2492ad0d30df309"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_func_t" ref="gaff0efa33d6ffbe1df2492ad0d30df309" args=")(snd_pcm_hook_t *hook)" -->
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<td class="memname">typedef int(* <a class="el" href="group___p_c_m___hook.html#gaff0efa33d6ffbe1df2492ad0d30df309">snd_pcm_hook_func_t</a>)(<a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> *hook)</td>
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<div class="memdoc">
<p>PCM hook callback function </p>
</div>
</div>
<a class="anchor" id="gae6b33860eeaf4eca00bdbef9383c1911"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_t" ref="gae6b33860eeaf4eca00bdbef9383c1911" args="" -->
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<td class="memname">typedef struct _snd_pcm_hook <a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a></td>
</tr>
</table>
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<div class="memdoc">
<p>PCM hook container </p>
</div>
</div>
<hr/><h2>Enumeration Type Documentation</h2>
<a class="anchor" id="ga57b6ba407d293017e116fa1b462a2411"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_type_t" ref="ga57b6ba407d293017e116fa1b462a2411" args="" -->
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<td class="memname">enum <a class="el" href="group___p_c_m___hook.html#ga57b6ba407d293017e116fa1b462a2411">snd_pcm_hook_type_t</a></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>type of pcm hook </p>
</div>
</div>
<hr/><h2>Function Documentation</h2>
<a class="anchor" id="ga89eed2fdcda68c1efae9180a3794d5ef"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_add" ref="ga89eed2fdcda68c1efae9180a3794d5ef" args="(snd_pcm_hook_t **hookp, snd_pcm_t *pcm, snd_pcm_hook_type_t type, snd_pcm_hook_func_t func, void *private_data)" -->
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<td class="memname">int snd_pcm_hook_add </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> ** </td>
<td class="paramname"> <em>hookp</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> * </td>
<td class="paramname"> <em>pcm</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#ga57b6ba407d293017e116fa1b462a2411">snd_pcm_hook_type_t</a> </td>
<td class="paramname"> <em>type</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#gaff0efa33d6ffbe1df2492ad0d30df309">snd_pcm_hook_func_t</a> </td>
<td class="paramname"> <em>func</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"> <em>private_data</em></td><td> </td>
</tr>
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<td></td>
<td>)</td>
<td></td><td></td><td></td>
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<p>Add a PCM hook at end of hooks chain. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>hookp</em> </td><td>Returned PCM hook handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>pcm</em> </td><td>PCM handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>type</em> </td><td>PCM hook type </td></tr>
<tr><td valign="top"></td><td valign="top"><em>func</em> </td><td>PCM hook callback function </td></tr>
<tr><td valign="top"></td><td valign="top"><em>private_data</em> </td><td>PCM hook private data </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success otherwise a negative error code</dd></dl>
<p>Warning: an hook callback function cannot remove an hook of the same type different from itself </p>
</div>
</div>
<a class="anchor" id="gacaec88e4b6cc2a45e7a805487acd64ed"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_get_pcm" ref="gacaec88e4b6cc2a45e7a805487acd64ed" args="(snd_pcm_hook_t *hook)" -->
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<td class="memname"><a class="el" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a>* snd_pcm_hook_get_pcm </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> * </td>
<td class="paramname"> <em>hook</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Get PCM handle for a PCM hook. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>hook</em> </td><td>PCM hook handle </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>PCM handle </dd></dl>
</div>
</div>
<a class="anchor" id="ga1eb467cd5ab11817edc2ed7df3608019"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_get_private" ref="ga1eb467cd5ab11817edc2ed7df3608019" args="(snd_pcm_hook_t *hook)" -->
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<td class="memname">void* snd_pcm_hook_get_private </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> * </td>
<td class="paramname"> <em>hook</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Get callback function private data for a PCM hook. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>hook</em> </td><td>PCM hook handle </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>callback function private data </dd></dl>
</div>
</div>
<a class="anchor" id="ga4c59ad440d2479f957b477b26b90e4b1"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_remove" ref="ga4c59ad440d2479f957b477b26b90e4b1" args="(snd_pcm_hook_t *hook)" -->
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<td class="memname">int snd_pcm_hook_remove </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> * </td>
<td class="paramname"> <em>hook</em></td>
<td> ) </td>
<td></td>
</tr>
</table>
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<div class="memdoc">
<p>Remove a PCM hook. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>hook</em> </td><td>PCM hook handle </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success otherwise a negative error code</dd></dl>
<p>Warning: an hook callback cannot remove an hook of the same type different from itself </p>
</div>
</div>
<a class="anchor" id="ga6930df3b750b3f62dee6846fb3f6a576"></a><!-- doxytag: member="pcm.h::snd_pcm_hook_set_private" ref="ga6930df3b750b3f62dee6846fb3f6a576" args="(snd_pcm_hook_t *hook, void *private_data)" -->
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<td class="memname">void snd_pcm_hook_set_private </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___p_c_m___hook.html#gae6b33860eeaf4eca00bdbef9383c1911">snd_pcm_hook_t</a> * </td>
<td class="paramname"> <em>hook</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"> <em>private_data</em></td><td> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Set callback function private data for a PCM hook. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>hook</em> </td><td>PCM hook handle </td></tr>
<tr><td valign="top"></td><td valign="top"><em>private_data</em> </td><td>The private data value </td></tr>
</table>
</dd>
</dl>
</div>
</div>
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