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<h1>Error handling</h1><table border="0" cellpadding="0" cellspacing="0">
<tr><td colspan="2"><h2>Defines</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#ga4e74ed65daac8e1737b7ec7b38d11ab4">SND_ERROR_BEGIN</a> 500000</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#gae24d4fe06c0a7478ebdaeeeca55d34c5">SND_ERROR_INCOMPATIBLE_VERSION</a> (SND_ERROR_BEGIN+0)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#ga07b06f3c54db1c1d382e02b59b4fb652">SND_ERROR_ALISP_NIL</a> (SND_ERROR_BEGIN+1)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#ga281420eb1344fe9f01d67d20c92457f0">SNDERR</a>(args...) <a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a>(__FILE__, __LINE__, __FUNCTION__, 0, ##args)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#ga6a6d50d5d5c51d971732e9925a226435">SYSERR</a>(args...) <a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a>(__FILE__, __LINE__, __FUNCTION__, errno, ##args)</td></tr>
<tr><td colspan="2"><h2>Typedefs</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">typedef void(* </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> )(const char *file, int line, const char *function, int err, const char *fmt,...)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Error handler callback. <a href="#gac24b8de276929202a3e3d0b45c20b6c1"></a><br/></td></tr>
<tr><td colspan="2"><h2>Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">const char * </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#ga182bbadf2349e11602bc531e8cf22f7e">snd_strerror</a> (int errnum)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Returns the message for an error code. <a href="#ga182bbadf2349e11602bc531e8cf22f7e"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#ga6ba1f0aa6c6bc5d335ab297d6019cb03">snd_lib_error_set_handler</a> (<a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> handler)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Sets the error handler. <a href="#ga6ba1f0aa6c6bc5d335ab297d6019cb03"></a><br/></td></tr>
<tr><td colspan="2"><h2>Variables</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a> = snd_lib_error_default</td></tr>
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<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>Error handling macros and functions. </p>
<hr/><h2>Define Documentation</h2>
<a class="anchor" id="ga07b06f3c54db1c1d382e02b59b4fb652"></a><!-- doxytag: member="error.h::SND_ERROR_ALISP_NIL" ref="ga07b06f3c54db1c1d382e02b59b4fb652" args="" -->
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<td class="memname">#define SND_ERROR_ALISP_NIL (SND_ERROR_BEGIN+1)</td>
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<p>Lisp encountered an error during acall. </p>
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<a class="anchor" id="ga4e74ed65daac8e1737b7ec7b38d11ab4"></a><!-- doxytag: member="error.h::SND_ERROR_BEGIN" ref="ga4e74ed65daac8e1737b7ec7b38d11ab4" args="" -->
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<td class="memname">#define SND_ERROR_BEGIN 500000</td>
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<p>Lower boundary of sound error codes. </p>
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</div>
<a class="anchor" id="gae24d4fe06c0a7478ebdaeeeca55d34c5"></a><!-- doxytag: member="error.h::SND_ERROR_INCOMPATIBLE_VERSION" ref="gae24d4fe06c0a7478ebdaeeeca55d34c5" args="" -->
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<td class="memname">#define SND_ERROR_INCOMPATIBLE_VERSION (SND_ERROR_BEGIN+0)</td>
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<div class="memdoc">
<p>Kernel/library protocols are not compatible. </p>
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<a class="anchor" id="ga281420eb1344fe9f01d67d20c92457f0"></a><!-- doxytag: member="error.h::SNDERR" ref="ga281420eb1344fe9f01d67d20c92457f0" args="(args...)" -->
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<td class="memname">#define SNDERR</td>
<td>(</td>
<td class="paramtype">args... </td>
<td class="paramname"></td>
<td> ) </td>
<td> <a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a>(__FILE__, __LINE__, __FUNCTION__, 0, ##args)</td>
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<div class="memdoc">
<p>Shows a sound error message. </p>
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</div>
<a class="anchor" id="ga6a6d50d5d5c51d971732e9925a226435"></a><!-- doxytag: member="error.h::SYSERR" ref="ga6a6d50d5d5c51d971732e9925a226435" args="(args...)" -->
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<td class="memname">#define SYSERR</td>
<td>(</td>
<td class="paramtype">args... </td>
<td class="paramname"></td>
<td> ) </td>
<td> <a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a>(__FILE__, __LINE__, __FUNCTION__, errno, ##args)</td>
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<p>Shows a system error message (related to <code>errno</code>). </p>
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<hr/><h2>Typedef Documentation</h2>
<a class="anchor" id="gac24b8de276929202a3e3d0b45c20b6c1"></a><!-- doxytag: member="error.h::snd_lib_error_handler_t" ref="gac24b8de276929202a3e3d0b45c20b6c1" args=")(const char *file, int line, const char *function, int err, const char *fmt,...)" -->
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<td class="memname">typedef void(* <a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a>)(const char *file, int line, const char *function, int err, const char *fmt,...)</td>
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<p>Error handler callback. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>file</em> </td><td>Source file name. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>line</em> </td><td>Line number. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>function</em> </td><td>Function name. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>err</em> </td><td>Value of <code>errno</code>, or 0 if not relevant. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>fmt</em> </td><td><code>printf(3)</code> format. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>...</em> </td><td><code>printf(3)</code> arguments.</td></tr>
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</dd>
</dl>
<p>A function of this type is called by the ALSA library when an error occurs. This function usually shows the message on the screen, and/or logs it. </p>
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<hr/><h2>Function Documentation</h2>
<a class="anchor" id="ga6ba1f0aa6c6bc5d335ab297d6019cb03"></a><!-- doxytag: member="error.h::snd_lib_error_set_handler" ref="ga6ba1f0aa6c6bc5d335ab297d6019cb03" args="(snd_lib_error_handler_t handler)" -->
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<td class="memname">int snd_lib_error_set_handler </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> </td>
<td class="paramname"> <em>handler</em></td>
<td> ) </td>
<td></td>
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<p>Sets the error handler. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>handler</em> </td><td>The pointer to the new error handler function.</td></tr>
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</dd>
</dl>
<p>This function sets a new error handler, or (if <code>handler</code> is <code>NULL</code>) the default one which prints the error messages to <code>stderr</code>. </p>
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<a class="anchor" id="ga182bbadf2349e11602bc531e8cf22f7e"></a><!-- doxytag: member="error.h::snd_strerror" ref="ga182bbadf2349e11602bc531e8cf22f7e" args="(int errnum)" -->
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<td class="memname">const char* snd_strerror </td>
<td>(</td>
<td class="paramtype">int </td>
<td class="paramname"> <em>errnum</em></td>
<td> ) </td>
<td></td>
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<p>Returns the message for an error code. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>errnum</em> </td><td>The error code number, which must be a system error code or an ALSA error code. </td></tr>
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<dl class="return"><dt><b>Returns:</b></dt><dd>The ASCII description of the given numeric error code. </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="_2test_2latency_8c-example.html#a5">/test/latency.c</a>, <a class="el" href="_2test_2pcm_8c-example.html#a16">/test/pcm.c</a>, <a class="el" href="_2test_2pcm__min_8c-example.html#a5">/test/pcm_min.c</a>, and <a class="el" href="_2test_2timer_8c-example.html#a3">/test/timer.c</a>.</dd>
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<hr/><h2>Variable Documentation</h2>
<a class="anchor" id="gad6a605072dcc056de5f86d67687d90a6"></a><!-- doxytag: member="error.c::snd_lib_error" ref="gad6a605072dcc056de5f86d67687d90a6" args="" -->
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<td class="memname"><a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> <a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a> = snd_lib_error_default</td>
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<p>Pointer to the error handler function. For internal use only. </p>
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<a class="anchor" id="gad6a605072dcc056de5f86d67687d90a6"></a><!-- doxytag: member="error.h::snd_lib_error" ref="gad6a605072dcc056de5f86d67687d90a6" args="" -->
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<td class="memname"><a class="el" href="group___error.html#gac24b8de276929202a3e3d0b45c20b6c1">snd_lib_error_handler_t</a> <a class="el" href="group___error.html#gad6a605072dcc056de5f86d67687d90a6">snd_lib_error</a></td>
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</table>
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<p>Pointer to the error handler function. For internal use only. </p>
</div>
</div>
</div>
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