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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>39.1. sunaudiodev — Access to Sun audio hardware — Python 2.7.5 documentation</title> <link rel="stylesheet" href="../_static/default.css" type="text/css" /> <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '../', VERSION: '2.7.5', COLLAPSE_INDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </script> <script type="text/javascript" src="../_static/jquery.js"></script> <script type="text/javascript" src="../_static/underscore.js"></script> <script type="text/javascript" src="../_static/doctools.js"></script> <script type="text/javascript" src="../_static/sidebar.js"></script> <link rel="search" type="application/opensearchdescription+xml" title="Search within Python 2.7.5 documentation" href="../_static/opensearch.xml"/> <link rel="author" title="About these documents" href="../about.html" /> <link rel="copyright" title="Copyright" href="../copyright.html" /> <link rel="top" title="Python 2.7.5 documentation" href="../index.html" /> <link rel="up" title="39. 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SunOS Specific Services" accesskey="P">previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="http://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.5 documentation</a> » </li> <li><a href="index.html" >The Python Standard Library</a> »</li> <li><a href="sun.html" accesskey="U">39. SunOS Specific Services</a> »</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body"> <div class="section" id="module-sunaudiodev"> <span id="sunaudiodev-access-to-sun-audio-hardware"></span><h1>39.1. <a class="reference internal" href="#module-sunaudiodev" title="sunaudiodev: Access to Sun audio hardware. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">sunaudiodev</span></tt></a> — Access to Sun audio hardware<a class="headerlink" href="#module-sunaudiodev" title="Permalink to this headline">¶</a></h1> <p class="deprecated"> <span class="versionmodified">Deprecated since version 2.6: </span>The <a class="reference internal" href="#module-sunaudiodev" title="sunaudiodev: Access to Sun audio hardware. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">sunaudiodev</span></tt></a> module has been removed in Python 3.</p> <p id="index-0">This module allows you to access the Sun audio interface. The Sun audio hardware is capable of recording and playing back audio data in u-LAW format with a sample rate of 8K per second. A full description can be found in the <em class="manpage">audio(7I)</em> manual page.</p> <p id="index-1">The module <a class="reference internal" href="#module-SUNAUDIODEV" title="SUNAUDIODEV: Constants for use with sunaudiodev. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">SUNAUDIODEV</span></tt></a> defines constants which may be used with this module.</p> <p>This module defines the following variables and functions:</p> <dl class="exception"> <dt id="sunaudiodev.error"> <em class="property">exception </em><tt class="descclassname">sunaudiodev.</tt><tt class="descname">error</tt><a class="headerlink" href="#sunaudiodev.error" title="Permalink to this definition">¶</a></dt> <dd><p>This exception is raised on all errors. The argument is a string describing what went wrong.</p> </dd></dl> <dl class="function"> <dt id="sunaudiodev.open"> <tt class="descclassname">sunaudiodev.</tt><tt class="descname">open</tt><big>(</big><em>mode</em><big>)</big><a class="headerlink" href="#sunaudiodev.open" title="Permalink to this definition">¶</a></dt> <dd><p>This function opens the audio device and returns a Sun audio device object. This object can then be used to do I/O on. The <em>mode</em> parameter is one of <tt class="docutils literal"><span class="pre">'r'</span></tt> for record-only access, <tt class="docutils literal"><span class="pre">'w'</span></tt> for play-only access, <tt class="docutils literal"><span class="pre">'rw'</span></tt> for both and <tt class="docutils literal"><span class="pre">'control'</span></tt> for access to the control device. Since only one process is allowed to have the recorder or player open at the same time it is a good idea to open the device only for the activity needed. See <em class="manpage">audio(7I)</em> for details.</p> <p>As per the manpage, this module first looks in the environment variable <tt class="docutils literal"><span class="pre">AUDIODEV</span></tt> for the base audio device filename. If not found, it falls back to <tt class="file docutils literal"><span class="pre">/dev/audio</span></tt>. The control device is calculated by appending “ctl” to the base audio device.</p> </dd></dl> <div class="section" id="audio-device-objects"> <span id="id1"></span><h2>39.1.1. Audio Device Objects<a class="headerlink" href="#audio-device-objects" title="Permalink to this headline">¶</a></h2> <p>The audio device objects are returned by <a class="reference internal" href="#sunaudiodev.open" title="sunaudiodev.open"><tt class="xref py py-func docutils literal"><span class="pre">open()</span></tt></a> define the following methods (except <tt class="docutils literal"><span class="pre">control</span></tt> objects which only provide <tt class="xref py py-meth docutils literal"><span class="pre">getinfo()</span></tt>, <tt class="xref py py-meth docutils literal"><span class="pre">setinfo()</span></tt>, <tt class="xref py py-meth docutils literal"><span class="pre">fileno()</span></tt>, and <tt class="xref py py-meth docutils literal"><span class="pre">drain()</span></tt>):</p> <dl class="method"> <dt> <tt class="descname">audio device.close()</tt></dt> <dd><p>This method explicitly closes the device. It is useful in situations where deleting the object does not immediately close it since there are other references to it. A closed device should not be used again.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.fileno()</tt></dt> <dd><p>Returns the file descriptor associated with the device. This can be used to set up <tt class="docutils literal"><span class="pre">SIGPOLL</span></tt> notification, as described below.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.drain()</tt></dt> <dd><p>This method waits until all pending output is processed and then returns. Calling this method is often not necessary: destroying the object will automatically close the audio device and this will do an implicit drain.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.flush()</tt></dt> <dd><p>This method discards all pending output. It can be used avoid the slow response to a user’s stop request (due to buffering of up to one second of sound).</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.getinfo()</tt></dt> <dd><p>This method retrieves status information like input and output volume, etc. and returns it in the form of an audio status object. This object has no methods but it contains a number of attributes describing the current device status. The names and meanings of the attributes are described in <tt class="docutils literal"><span class="pre"><sun/audioio.h></span></tt> and in the <em class="manpage">audio(7I)</em> manual page. Member names are slightly different from their C counterparts: a status object is only a single structure. Members of the <tt class="xref c c-data docutils literal"><span class="pre">play</span></tt> substructure have <tt class="docutils literal"><span class="pre">o_</span></tt> prepended to their name and members of the <tt class="xref c c-data docutils literal"><span class="pre">record</span></tt> structure have <tt class="docutils literal"><span class="pre">i_</span></tt>. So, the C member <tt class="xref c c-data docutils literal"><span class="pre">play.sample_rate</span></tt> is accessed as <tt class="xref py py-attr docutils literal"><span class="pre">o_sample_rate</span></tt>, <tt class="xref c c-data docutils literal"><span class="pre">record.gain</span></tt> as <tt class="xref py py-attr docutils literal"><span class="pre">i_gain</span></tt> and <tt class="xref c c-data docutils literal"><span class="pre">monitor_gain</span></tt> plainly as <tt class="xref py py-attr docutils literal"><span class="pre">monitor_gain</span></tt>.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.ibufcount()</tt></dt> <dd><p>This method returns the number of samples that are buffered on the recording side, i.e. the program will not block on a <tt class="xref py py-func docutils literal"><span class="pre">read()</span></tt> call of so many samples.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.obufcount()</tt></dt> <dd><p>This method returns the number of samples buffered on the playback side. Unfortunately, this number cannot be used to determine a number of samples that can be written without blocking since the kernel output queue length seems to be variable.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.read(size)</tt></dt> <dd><p>This method reads <em>size</em> samples from the audio input and returns them as a Python string. The function blocks until enough data is available.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.setinfo(status)</tt></dt> <dd><p>This method sets the audio device status parameters. The <em>status</em> parameter is an device status object as returned by <tt class="xref py py-func docutils literal"><span class="pre">getinfo()</span></tt> and possibly modified by the program.</p> </dd></dl> <dl class="method"> <dt> <tt class="descname">audio device.write(samples)</tt></dt> <dd><p>Write is passed a Python string containing audio samples to be played. If there is enough buffer space free it will immediately return, otherwise it will block.</p> </dd></dl> <p>The audio device supports asynchronous notification of various events, through the SIGPOLL signal. Here’s an example of how you might enable this in Python:</p> <div class="highlight-python"><div class="highlight"><pre><span class="k">def</span> <span class="nf">handle_sigpoll</span><span class="p">(</span><span class="n">signum</span><span class="p">,</span> <span class="n">frame</span><span class="p">):</span> <span class="k">print</span> <span class="s">'I got a SIGPOLL update'</span> <span class="kn">import</span> <span class="nn">fcntl</span><span class="o">,</span> <span class="nn">signal</span><span class="o">,</span> <span class="nn">STROPTS</span> <span class="n">signal</span><span class="o">.</span><span class="n">signal</span><span class="p">(</span><span class="n">signal</span><span class="o">.</span><span class="n">SIGPOLL</span><span class="p">,</span> <span class="n">handle_sigpoll</span><span class="p">)</span> <span class="n">fcntl</span><span class="o">.</span><span class="n">ioctl</span><span class="p">(</span><span class="n">audio_obj</span><span class="o">.</span><span class="n">fileno</span><span class="p">(),</span> <span class="n">STROPTS</span><span class="o">.</span><span class="n">I_SETSIG</span><span class="p">,</span> <span class="n">STROPTS</span><span class="o">.</span><span class="n">S_MSG</span><span class="p">)</span> </pre></div> </div> </div> </div> <div class="section" id="module-SUNAUDIODEV"> <span id="sunaudiodev-constants-used-with-sunaudiodev"></span><h1>39.2. <a class="reference internal" href="#module-SUNAUDIODEV" title="SUNAUDIODEV: Constants for use with sunaudiodev. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">SUNAUDIODEV</span></tt></a> — Constants used with <a class="reference internal" href="#module-sunaudiodev" title="sunaudiodev: Access to Sun audio hardware. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">sunaudiodev</span></tt></a><a class="headerlink" href="#module-SUNAUDIODEV" title="Permalink to this headline">¶</a></h1> <p class="deprecated"> <span class="versionmodified">Deprecated since version 2.6: </span>The <a class="reference internal" href="#module-SUNAUDIODEV" title="SUNAUDIODEV: Constants for use with sunaudiodev. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">SUNAUDIODEV</span></tt></a> module has been removed in Python 3.</p> <p id="index-2">This is a companion module to <a class="reference internal" href="#module-sunaudiodev" title="sunaudiodev: Access to Sun audio hardware. (deprecated) (SunOS)"><tt class="xref py py-mod docutils literal"><span class="pre">sunaudiodev</span></tt></a> which defines useful symbolic constants like <tt class="xref py py-const docutils literal"><span class="pre">MIN_GAIN</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">MAX_GAIN</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">SPEAKER</span></tt>, etc. The names of the constants are the same names as used in the C include file <tt class="docutils literal"><span class="pre"><sun/audioio.h></span></tt>, with the leading string <tt class="docutils literal"><span class="pre">AUDIO_</span></tt> stripped.</p> </div> </div> </div> </div> <div class="sphinxsidebar"> <div class="sphinxsidebarwrapper"> <h3><a href="../contents.html">Table Of Contents</a></h3> <ul> <li><a class="reference internal" href="#">39.1. <tt class="docutils literal"><span class="pre">sunaudiodev</span></tt> — Access to Sun audio hardware</a><ul> <li><a class="reference internal" href="#audio-device-objects">39.1.1. Audio Device Objects</a></li> </ul> </li> <li><a class="reference internal" href="#module-SUNAUDIODEV">39.2. <tt class="docutils literal"><span class="pre">SUNAUDIODEV</span></tt> — Constants used with <tt class="docutils literal"><span class="pre">sunaudiodev</span></tt></a></li> </ul> <h4>Previous topic</h4> <p class="topless"><a href="sun.html" title="previous chapter">39. SunOS Specific Services</a></p> <h4>Next topic</h4> <p class="topless"><a href="undoc.html" title="next chapter">40. 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