1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>snd_ctl_activate_id</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The ALSA Driver API"><link rel="up" href="ch03.html#idp1094472508" title="General Control Interface"><link rel="prev" href="API-snd-ctl-remove-id.html" title="snd_ctl_remove_id"><link rel="next" href="API-snd-ctl-rename-id.html" title="snd_ctl_rename_id"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">snd_ctl_activate_id</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-snd-ctl-remove-id.html">Prev</a>&#160;</td><th width="60%" align="center">General Control Interface</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-snd-ctl-rename-id.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-snd-ctl-activate-id"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>snd_ctl_activate_id &#8212; 
2     activate/inactivate the control of the given id
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">snd_ctl_activate_id </b>(</code></td><td>struct snd_card * <var class="pdparam">card</var>, </td></tr><tr><td>&#160;</td><td>struct snd_ctl_elem_id * <var class="pdparam">id</var>, </td></tr><tr><td>&#160;</td><td>int <var class="pdparam">active</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1094546412"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>card</code></em></span></dt><dd><p>
4     the card instance
5    </p></dd><dt><span class="term"><em class="parameter"><code>id</code></em></span></dt><dd><p>
6     the control id to activate/inactivate
7    </p></dd><dt><span class="term"><em class="parameter"><code>active</code></em></span></dt><dd><p>
8     non-zero to activate
9    </p></dd></dl></div></div><div class="refsect1"><a name="idp1094550076"></a><h2>Description</h2><p>
10   Finds the control instance with the given id, and activate or
11   inactivate the control together with notification, if changed.
12   The given ID data is filled with full information.
13</p></div><div class="refsect1"><a name="idp1094550860"></a><h2>Return</h2><p>
14   0 if unchanged, 1 if changed, or a negative error code on failure.
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