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<h1>/test/pcm_min.c</h1><div class="fragment"><pre class="fragment"><span class="comment">/*</span>
<span class="comment"> * This extra small demo sends a random samples to your speakers.</span>
<span class="comment"> */</span>
<span class="preprocessor">#include "../include/asoundlib.h"</span>
<span class="keyword">static</span> <span class="keywordtype">char</span> *device = <span class="stringliteral">"default"</span>; <span class="comment">/* playback device */</span>
<a name="a0"></a><a class="code" href="group___output.html#ga49729cc6454539495c1f5b6e95cd474a" title="Internal structure for an output object.">snd_output_t</a> *output = NULL;
<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> buffer[16*1024]; <span class="comment">/* some random data */</span>
<span class="keywordtype">int</span> main(<span class="keywordtype">void</span>)
{
<span class="keywordtype">int</span> err;
<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i;
<a name="a1"></a><a class="code" href="group___p_c_m.html#ga919e634deecd855b6e2e15174e70d3ea">snd_pcm_t</a> *handle;
<a name="a2"></a><a class="code" href="group___p_c_m.html#ga71cdfa37e258d2210b8bd0216bf0c36c">snd_pcm_sframes_t</a> frames;
<span class="keywordflow">for</span> (i = 0; i < <span class="keyword">sizeof</span>(buffer); i++)
buffer[i] = random() & 0xff;
<span class="keywordflow">if</span> ((err = <a name="a3"></a><a class="code" href="group___p_c_m.html#ga8340c7dc0ac37f37afe5e7c21d6c528b" title="Opens a PCM.">snd_pcm_open</a>(&handle, device, <a name="a4"></a><a class="code" href="group___p_c_m.html#ggac23b43ff55add78638e503b9cc892c24a57a2b920dbc34173479fc9036cfc78a1">SND_PCM_STREAM_PLAYBACK</a>, 0)) < 0) {
printf(<span class="stringliteral">"Playback open error: %s\n"</span>, <a name="a5"></a><a class="code" href="group___error.html#ga182bbadf2349e11602bc531e8cf22f7e" title="Returns the message for an error code.">snd_strerror</a>(err));
exit(EXIT_FAILURE);
}
<span class="keywordflow">if</span> ((err = <a name="a6"></a><a class="code" href="group___p_c_m.html#ga45d50841b307f2156fce1857bfac228c" title="Set the hardware and software parameters in a simple way.">snd_pcm_set_params</a>(handle,
<a name="a7"></a><a class="code" href="group___p_c_m.html#ggaa14b7f26877a812acbb39811364177f8ad5856f97113926836a7c6651cb8864a3">SND_PCM_FORMAT_U8</a>,
<a name="a8"></a><a class="code" href="group___p_c_m.html#gga661221ba5e8f1d6eaf4ab8e2da57cc1aa72a970ed6e676ab0fd9f3c3d36737e0a">SND_PCM_ACCESS_RW_INTERLEAVED</a>,
1,
48000,
1,
500000)) < 0) { <span class="comment">/* 0.5sec */</span>
printf(<span class="stringliteral">"Playback open error: %s\n"</span>, <a class="code" href="group___error.html#ga182bbadf2349e11602bc531e8cf22f7e" title="Returns the message for an error code.">snd_strerror</a>(err));
exit(EXIT_FAILURE);
}
<span class="keywordflow">for</span> (i = 0; i < 16; i++) {
frames = <a name="a9"></a><a class="code" href="group___p_c_m.html#gabc748a500743713eafa960c7d104ca6f" title="Write interleaved frames to a PCM.">snd_pcm_writei</a>(handle, buffer, <span class="keyword">sizeof</span>(buffer));
<span class="keywordflow">if</span> (frames < 0)
frames = <a name="a10"></a><a class="code" href="group___p_c_m.html#ga2157aaeb6fc14da3f040d76591f9d3b1" title="Recover the stream state from an error or suspend.">snd_pcm_recover</a>(handle, frames, 0);
<span class="keywordflow">if</span> (frames < 0) {
printf(<span class="stringliteral">"snd_pcm_writei failed: %s\n"</span>, <a class="code" href="group___error.html#ga182bbadf2349e11602bc531e8cf22f7e" title="Returns the message for an error code.">snd_strerror</a>(err));
<span class="keywordflow">break</span>;
}
<span class="keywordflow">if</span> (frames > 0 && frames < (<span class="keywordtype">long</span>)<span class="keyword">sizeof</span>(buffer))
printf(<span class="stringliteral">"Short write (expected %li, wrote %li)\n"</span>, (<span class="keywordtype">long</span>)<span class="keyword">sizeof</span>(buffer), frames);
}
<a name="a11"></a><a class="code" href="group___p_c_m.html#ga042aba7262a4cbb4d444b6fc08cb7124" title="close PCM handle">snd_pcm_close</a>(handle);
<span class="keywordflow">return</span> 0;
}
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