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<h2><span class="refentrytitle"><a name="gstreamer-GstPoll.top_of_page"></a>GstPoll</span></h2>
<p>GstPoll — Keep track of file descriptors and make it possible
to wait on them in a cancellable way</p>
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<div class="refsect1">
<a name="gstreamer-GstPoll.functions"></a><h2>Functions</h2>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-add-fd" title="gst_poll_add_fd ()">gst_poll_add_fd</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-can-read" title="gst_poll_fd_can_read ()">gst_poll_fd_can_read</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-can-write" title="gst_poll_fd_can_write ()">gst_poll_fd_can_write</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-ctl-read" title="gst_poll_fd_ctl_read ()">gst_poll_fd_ctl_read</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-ctl-write" title="gst_poll_fd_ctl_write ()">gst_poll_fd_ctl_write</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-has-closed" title="gst_poll_fd_has_closed ()">gst_poll_fd_has_closed</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-has-error" title="gst_poll_fd_has_error ()">gst_poll_fd_has_error</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-ignored" title="gst_poll_fd_ignored ()">gst_poll_fd_ignored</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-init" title="gst_poll_fd_init ()">gst_poll_fd_init</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-free" title="gst_poll_free ()">gst_poll_free</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="returnvalue">GstPoll</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-new" title="gst_poll_new ()">gst_poll_new</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="returnvalue">GstPoll</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-new-timer" title="gst_poll_new_timer ()">gst_poll_new_timer</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-get-read-gpollfd" title="gst_poll_get_read_gpollfd ()">gst_poll_get_read_gpollfd</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-remove-fd" title="gst_poll_remove_fd ()">gst_poll_remove_fd</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-restart" title="gst_poll_restart ()">gst_poll_restart</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-set-controllable" title="gst_poll_set_controllable ()">gst_poll_set_controllable</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-set-flushing" title="gst_poll_set_flushing ()">gst_poll_set_flushing</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gint"><span class="returnvalue">gint</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()">gst_poll_wait</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-read-control" title="gst_poll_read_control ()">gst_poll_read_control</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstPoll.html#gst-poll-write-control" title="gst_poll_write_control ()">gst_poll_write_control</a> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gstreamer-GstPoll.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody>
<tr>
<td class="datatype_keyword"> </td>
<td class="function_name"><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll">GstPoll</a></td>
</tr>
<tr>
<td class="datatype_keyword"> </td>
<td class="function_name"><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD">GstPollFD</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="gstreamer-GstPoll.html#GST-POLL-FD-INIT:CAPS" title="GST_POLL_FD_INIT">GST_POLL_FD_INIT</a></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gstreamer-GstPoll.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include &lt;gst/gst.h&gt;
</pre>
</div>
<div class="refsect1">
<a name="gstreamer-GstPoll.description"></a><h2>Description</h2>
<p>A <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> keeps track of file descriptors much like fd_set (used with
<code class="function">select()</code>) or a struct pollfd array (used with <code class="function">poll()</code>). Once created with
<a class="link" href="gstreamer-GstPoll.html#gst-poll-new" title="gst_poll_new ()"><code class="function">gst_poll_new()</code></a>, the set can be used to wait for file descriptors to be
readable and/or writable. It is possible to make this wait be controlled
by specifying <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> for the <em class="parameter"><code>controllable</code></em>
flag when creating the set (or
later calling <a class="link" href="gstreamer-GstPoll.html#gst-poll-set-controllable" title="gst_poll_set_controllable ()"><code class="function">gst_poll_set_controllable()</code></a>).</p>
<p>New file descriptors are added to the set using <a class="link" href="gstreamer-GstPoll.html#gst-poll-add-fd" title="gst_poll_add_fd ()"><code class="function">gst_poll_add_fd()</code></a>, and
removed using <a class="link" href="gstreamer-GstPoll.html#gst-poll-remove-fd" title="gst_poll_remove_fd ()"><code class="function">gst_poll_remove_fd()</code></a>. Controlling which file descriptors
should be waited for to become readable and/or writable are done using
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-ctl-read" title="gst_poll_fd_ctl_read ()"><code class="function">gst_poll_fd_ctl_read()</code></a> and <a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-ctl-write" title="gst_poll_fd_ctl_write ()"><code class="function">gst_poll_fd_ctl_write()</code></a>.</p>
<p>Use <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> to wait for the file descriptors to actually become
readable and/or writable, or to timeout if no file descriptor is available
in time. The wait can be controlled by calling <a class="link" href="gstreamer-GstPoll.html#gst-poll-restart" title="gst_poll_restart ()"><code class="function">gst_poll_restart()</code></a> and
<a class="link" href="gstreamer-GstPoll.html#gst-poll-set-flushing" title="gst_poll_set_flushing ()"><code class="function">gst_poll_set_flushing()</code></a>.</p>
<p>Once the file descriptor set has been waited for, one can use
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-has-closed" title="gst_poll_fd_has_closed ()"><code class="function">gst_poll_fd_has_closed()</code></a> to see if the file descriptor has been closed,
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-has-error" title="gst_poll_fd_has_error ()"><code class="function">gst_poll_fd_has_error()</code></a> to see if it has generated an error,
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-can-read" title="gst_poll_fd_can_read ()"><code class="function">gst_poll_fd_can_read()</code></a> to see if it is possible to read from the file
descriptor, and <a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-can-write" title="gst_poll_fd_can_write ()"><code class="function">gst_poll_fd_can_write()</code></a> to see if it is possible to
write to it.</p>
</div>
<div class="refsect1">
<a name="gstreamer-GstPoll.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="gst-poll-add-fd"></a><h3>gst_poll_add_fd ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_add_fd (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Add a file descriptor to the file descriptor set.</p>
<div class="refsect3">
<a name="id-1.3.40.7.2.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.2.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the file descriptor was successfully added to the set.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-can-read"></a><h3>gst_poll_fd_can_read ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_fd_can_read (<em class="parameter"><code>const <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Check if <em class="parameter"><code>fd</code></em>
in <em class="parameter"><code>set</code></em>
has data to be read.</p>
<div class="refsect3">
<a name="id-1.3.40.7.3.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.3.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the descriptor has data to be read.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-can-write"></a><h3>gst_poll_fd_can_write ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_fd_can_write (<em class="parameter"><code>const <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Check if <em class="parameter"><code>fd</code></em>
in <em class="parameter"><code>set</code></em>
can be used for writing.</p>
<div class="refsect3">
<a name="id-1.3.40.7.4.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.4.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the descriptor can be used for writing.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-ctl-read"></a><h3>gst_poll_fd_ctl_read ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_fd_ctl_read (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> active</code></em>);</pre>
<p>Control whether the descriptor <em class="parameter"><code>fd</code></em>
in <em class="parameter"><code>set</code></em>
will be monitored for
readability.</p>
<div class="refsect3">
<a name="id-1.3.40.7.5.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>active</p></td>
<td class="parameter_description"><p>a new status.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.5.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the descriptor was successfully updated.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-ctl-write"></a><h3>gst_poll_fd_ctl_write ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_fd_ctl_write (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> active</code></em>);</pre>
<p>Control whether the descriptor <em class="parameter"><code>fd</code></em>
in <em class="parameter"><code>set</code></em>
will be monitored for
writability.</p>
<div class="refsect3">
<a name="id-1.3.40.7.6.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>active</p></td>
<td class="parameter_description"><p>a new status.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.6.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the descriptor was successfully updated.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-has-closed"></a><h3>gst_poll_fd_has_closed ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_fd_has_closed (<em class="parameter"><code>const <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Check if <em class="parameter"><code>fd</code></em>
in <em class="parameter"><code>set</code></em>
has closed the connection.</p>
<div class="refsect3">
<a name="id-1.3.40.7.7.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.7.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the connection was closed.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-has-error"></a><h3>gst_poll_fd_has_error ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_fd_has_error (<em class="parameter"><code>const <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Check if <em class="parameter"><code>fd</code></em>
in <em class="parameter"><code>set</code></em>
has an error.</p>
<div class="refsect3">
<a name="id-1.3.40.7.8.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.8.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the descriptor has an error.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-ignored"></a><h3>gst_poll_fd_ignored ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_poll_fd_ignored (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Mark <em class="parameter"><code>fd</code></em>
as ignored so that the next call to <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> will yield
the same result for <em class="parameter"><code>fd</code></em>
as last time. This function must be called if no
operation (read/write/recv/send/etc.) will be performed on <em class="parameter"><code>fd</code></em>
before
the next call to <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a>.</p>
<p>The reason why this is needed is because the underlying implementation
might not allow querying the fd more than once between calls to one of
the re-enabling operations.</p>
<div class="refsect3">
<a name="id-1.3.40.7.9.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-fd-init"></a><h3>gst_poll_fd_init ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_poll_fd_init (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Initializes <em class="parameter"><code>fd</code></em>
. Alternatively you can initialize it with
<a class="link" href="gstreamer-GstPoll.html#GST-POLL-FD-INIT:CAPS" title="GST_POLL_FD_INIT"><span class="type">GST_POLL_FD_INIT</span></a>.</p>
<div class="refsect3">
<a name="id-1.3.40.7.10.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-free"></a><h3>gst_poll_free ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_poll_free (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>);</pre>
<p>Free a file descriptor set.</p>
<div class="refsect3">
<a name="id-1.3.40.7.11.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p> a file descriptor set. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span></td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-new"></a><h3>gst_poll_new ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="returnvalue">GstPoll</span></a> *
gst_poll_new (<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> controllable</code></em>);</pre>
<p>Create a new file descriptor set. If <em class="parameter"><code>controllable</code></em>
, it
is possible to restart or flush a call to <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> with
<a class="link" href="gstreamer-GstPoll.html#gst-poll-restart" title="gst_poll_restart ()"><code class="function">gst_poll_restart()</code></a> and <a class="link" href="gstreamer-GstPoll.html#gst-poll-set-flushing" title="gst_poll_set_flushing ()"><code class="function">gst_poll_set_flushing()</code></a> respectively.</p>
<p>Free-function: gst_poll_free</p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
<div class="refsect3">
<a name="id-1.3.40.7.12.7"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>controllable</p></td>
<td class="parameter_description"><p>whether it should be possible to control a wait.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.12.8"></a><h4>Returns</h4>
<p> a new <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>, or <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> in
case of an error. Free with <a class="link" href="gstreamer-GstPoll.html#gst-poll-free" title="gst_poll_free ()"><code class="function">gst_poll_free()</code></a>. </p>
<p><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>][<acronym title="NULL may be passed as the value in, out, in-out; or as a return value."><span class="acronym">nullable</span></acronym>]</span></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-new-timer"></a><h3>gst_poll_new_timer ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="returnvalue">GstPoll</span></a> *
gst_poll_new_timer (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>Create a new poll object that can be used for scheduling cancellable
timeouts.</p>
<p>A timeout is performed with <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a>. Multiple timeouts can be
performed from different threads. </p>
<p>Free-function: gst_poll_free</p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
<div class="refsect3">
<a name="id-1.3.40.7.13.8"></a><h4>Returns</h4>
<p> a new <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>, or <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> in
case of an error. Free with <a class="link" href="gstreamer-GstPoll.html#gst-poll-free" title="gst_poll_free ()"><code class="function">gst_poll_free()</code></a>. </p>
<p><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>][<acronym title="NULL may be passed as the value in, out, in-out; or as a return value."><span class="acronym">nullable</span></acronym>]</span></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-get-read-gpollfd"></a><h3>gst_poll_get_read_gpollfd ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_poll_get_read_gpollfd (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-The-Main-Event-Loop.html#GPollFD"><span class="type">GPollFD</span></a> *fd</code></em>);</pre>
<p>Get a GPollFD for the reading part of the control socket. This is useful when
integrating with a GSource and GMainLoop.</p>
<div class="refsect3">
<a name="id-1.3.40.7.14.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a <a href="https://developer.gnome.org/glib/unstable/glib-The-Main-Event-Loop.html#GPollFD"><span class="type">GPollFD</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-remove-fd"></a><h3>gst_poll_remove_fd ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_remove_fd (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> *fd</code></em>);</pre>
<p>Remove a file descriptor from the file descriptor set.</p>
<div class="refsect3">
<a name="id-1.3.40.7.15.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a file descriptor set.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fd</p></td>
<td class="parameter_description"><p>a file descriptor.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.15.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the file descriptor was successfully removed from the set.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-restart"></a><h3>gst_poll_restart ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_poll_restart (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>);</pre>
<p>Restart any <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> that is in progress. This function is typically
used after adding or removing descriptors to <em class="parameter"><code>set</code></em>
.</p>
<p>If <em class="parameter"><code>set</code></em>
is not controllable, then this call will have no effect.</p>
<div class="refsect3">
<a name="id-1.3.40.7.16.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-set-controllable"></a><h3>gst_poll_set_controllable ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_set_controllable (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> controllable</code></em>);</pre>
<p>When <em class="parameter"><code>controllable</code></em>
is <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a>, this function ensures that future calls to
<a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> will be affected by <a class="link" href="gstreamer-GstPoll.html#gst-poll-restart" title="gst_poll_restart ()"><code class="function">gst_poll_restart()</code></a> and
<a class="link" href="gstreamer-GstPoll.html#gst-poll-set-flushing" title="gst_poll_set_flushing ()"><code class="function">gst_poll_set_flushing()</code></a>.</p>
<div class="refsect3">
<a name="id-1.3.40.7.17.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>controllable</p></td>
<td class="parameter_description"><p>new controllable state.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.17.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the controllability of <em class="parameter"><code>set</code></em>
could be updated.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-set-flushing"></a><h3>gst_poll_set_flushing ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_poll_set_flushing (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> flushing</code></em>);</pre>
<p>When <em class="parameter"><code>flushing</code></em>
is <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a>, this function ensures that current and future calls
to <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> will return -1, with errno set to EBUSY.</p>
<p>Unsetting the flushing state will restore normal operation of <em class="parameter"><code>set</code></em>
.</p>
<div class="refsect3">
<a name="id-1.3.40.7.18.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>flushing</p></td>
<td class="parameter_description"><p>new flushing state.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-wait"></a><h3>gst_poll_wait ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gint"><span class="returnvalue">gint</span></a>
gst_poll_wait (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>,
<em class="parameter"><code><a class="link" href="GstClock.html#GstClockTime" title="GstClockTime"><span class="type">GstClockTime</span></a> timeout</code></em>);</pre>
<p>Wait for activity on the file descriptors in <em class="parameter"><code>set</code></em>
. This function waits up to
the specified <em class="parameter"><code>timeout</code></em>
. A timeout of <a class="link" href="GstClock.html#GST-CLOCK-TIME-NONE:CAPS" title="GST_CLOCK_TIME_NONE"><span class="type">GST_CLOCK_TIME_NONE</span></a> waits forever.</p>
<p>For <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> objects created with <a class="link" href="gstreamer-GstPoll.html#gst-poll-new" title="gst_poll_new ()"><code class="function">gst_poll_new()</code></a>, this function can only be
called from a single thread at a time. If called from multiple threads,
-1 will be returned with errno set to EPERM.</p>
<p>This is not true for timer <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> objects created with
<a class="link" href="gstreamer-GstPoll.html#gst-poll-new-timer" title="gst_poll_new_timer ()"><code class="function">gst_poll_new_timer()</code></a>, where it is allowed to have multiple threads waiting
simultaneously.</p>
<div class="refsect3">
<a name="id-1.3.40.7.19.7"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>timeout</p></td>
<td class="parameter_description"><p>a timeout in nanoseconds.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.19.8"></a><h4>Returns</h4>
<p> The number of <a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> in <em class="parameter"><code>set</code></em>
that have activity or 0 when no
activity was detected after <em class="parameter"><code>timeout</code></em>
. If an error occurs, -1 is returned
and errno is set.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-read-control"></a><h3>gst_poll_read_control ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_read_control (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>);</pre>
<p>Read a byte from the control socket of the controllable <em class="parameter"><code>set</code></em>
.
This function is mostly useful for timer <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> objects created with
<a class="link" href="gstreamer-GstPoll.html#gst-poll-new-timer" title="gst_poll_new_timer ()"><code class="function">gst_poll_new_timer()</code></a>.</p>
<div class="refsect3">
<a name="id-1.3.40.7.20.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.20.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> on success. <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> when <em class="parameter"><code>set</code></em>
is not controllable or when there
was no byte to read.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-poll-write-control"></a><h3>gst_poll_write_control ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_poll_write_control (<em class="parameter"><code><a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> *set</code></em>);</pre>
<p>Write a byte to the control socket of the controllable <em class="parameter"><code>set</code></em>
.
This function is mostly useful for timer <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a> objects created with
<a class="link" href="gstreamer-GstPoll.html#gst-poll-new-timer" title="gst_poll_new_timer ()"><code class="function">gst_poll_new_timer()</code></a>. </p>
<p>It will make any current and future <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> function return with
1, meaning the control socket is set. After an equal amount of calls to
<a class="link" href="gstreamer-GstPoll.html#gst-poll-read-control" title="gst_poll_read_control ()"><code class="function">gst_poll_read_control()</code></a> have been performed, calls to <a class="link" href="gstreamer-GstPoll.html#gst-poll-wait" title="gst_poll_wait ()"><code class="function">gst_poll_wait()</code></a> will
block again until their timeout expired.</p>
<div class="refsect3">
<a name="id-1.3.40.7.21.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>set</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstPoll.html#GstPoll" title="GstPoll"><span class="type">GstPoll</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.3.40.7.21.7"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> on success. <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> when <em class="parameter"><code>set</code></em>
is not controllable or when the
byte could not be written.</p>
</div>
</div>
</div>
<div class="refsect1">
<a name="gstreamer-GstPoll.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GstPoll"></a><h3>GstPoll</h3>
<pre class="programlisting">typedef struct _GstPoll GstPoll;</pre>
<p>A set of file/network descriptors.</p>
</div>
<hr>
<div class="refsect2">
<a name="GstPollFD"></a><h3>GstPollFD</h3>
<pre class="programlisting">typedef struct {
int fd;
} GstPollFD;
</pre>
<p>A file descriptor object.</p>
<div class="refsect3">
<a name="id-1.3.40.8.3.5"></a><h4>Members</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="300px" class="struct_members_name">
<col class="struct_members_description">
<col width="200px" class="struct_members_annotations">
</colgroup>
<tbody><tr>
<td class="struct_member_name"><p><span class="type">int</span> <em class="structfield"><code><a name="GstPollFD.fd"></a>fd</code></em>;</p></td>
<td class="struct_member_description"><p>a file descriptor</p></td>
<td class="struct_member_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-POLL-FD-INIT:CAPS"></a><h3>GST_POLL_FD_INIT</h3>
<pre class="programlisting">#define GST_POLL_FD_INIT { -1, -1 }
</pre>
<p>A <a class="link" href="gstreamer-GstPoll.html#GstPollFD" title="GstPollFD"><span class="type">GstPollFD</span></a> must be initialized with this macro, before it can be
used. This macro can used be to initialize a variable, but it cannot
be assigned to a variable. In that case you have to use
<a class="link" href="gstreamer-GstPoll.html#gst-poll-fd-init" title="gst_poll_fd_init ()"><code class="function">gst_poll_fd_init()</code></a>.</p>
</div>
</div>
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