1<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>v4l2_ctrl_add_handler</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux Device Drivers"><link rel="up" href="mediadev.html#id-1.8.2" title="Video2Linux devices"><link rel="prev" href="API-v4l2-ctrl-add-ctrl.html" title="v4l2_ctrl_add_ctrl"><link rel="next" href="API-v4l2-ctrl-radio-filter.html" title="v4l2_ctrl_radio_filter"></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">v4l2_ctrl_add_handler</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-v4l2-ctrl-add-ctrl.html">Prev</a> </td><th width="60%" align="center">Video2Linux devices</th><td width="20%" align="right"> <a accesskey="n" href="API-v4l2-ctrl-radio-filter.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-v4l2-ctrl-add-handler"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>v4l2_ctrl_add_handler — 2 Add all controls from handler <em class="parameter"><code>add</code></em> to handler <em class="parameter"><code>hdl</code></em>. 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">v4l2_ctrl_add_handler </b>(</code></td><td><a class="link" href="API-struct-v4l2-ctrl-handler.html" title="struct v4l2_ctrl_handler">struct v4l2_ctrl_handler</a> * <var class="pdparam">hdl</var>, </td></tr><tr><td> </td><td><a class="link" href="API-struct-v4l2-ctrl-handler.html" title="struct v4l2_ctrl_handler">struct v4l2_ctrl_handler</a> * <var class="pdparam">add</var>, </td></tr><tr><td> </td><td>bool (*<var class="pdparam">filter</var>) 4 <code>(</code>const struct v4l2_ctrl *ctrl<code>)</code><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="id-1.8.2.32.5"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>hdl</code></em></span></dt><dd><p> 5 The control handler. 6 </p></dd><dt><span class="term"><em class="parameter"><code>add</code></em></span></dt><dd><p> 7 The control handler whose controls you want to add to 8 the <em class="parameter"><code>hdl</code></em> control handler. 9 </p></dd><dt><span class="term"><em class="parameter"><code>filter</code></em></span></dt><dd><p> 10 This function will filter which controls should be added. 11 </p></dd></dl></div></div><div class="refsect1"><a name="id-1.8.2.32.6"></a><h2>Description</h2><p> 12 Does nothing if either of the two handlers is a NULL pointer. 13 If <em class="parameter"><code>filter</code></em> is NULL, then all controls are added. Otherwise only those 14 controls for which <em class="parameter"><code>filter</code></em> returns true will be added. 15 In case of an error <em class="parameter"><code>hdl</code></em>->error will be set to the error code (if it 16 wasn't set already). 17</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-v4l2-ctrl-add-ctrl.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="mediadev.html#id-1.8.2">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="API-v4l2-ctrl-radio-filter.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">v4l2_ctrl_add_ctrl</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span class="phrase">v4l2_ctrl_radio_filter</span></td></tr></table></div></body></html> 18