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Diffstat (limited to 'Documentation/DocBook/media/v4l/cec-func-poll.xml')
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diff --git a/Documentation/DocBook/media/v4l/cec-func-poll.xml b/Documentation/DocBook/media/v4l/cec-func-poll.xml deleted file mode 100644 index 1bddbde0142d..000000000000 --- a/Documentation/DocBook/media/v4l/cec-func-poll.xml +++ /dev/null @@ -1,94 +0,0 @@ -<refentry id="cec-func-poll"> - <refmeta> - <refentrytitle>cec poll()</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>cec-poll</refname> - <refpurpose>Wait for some event on a file descriptor</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <sys/poll.h></funcsynopsisinfo> - <funcprototype> - <funcdef>int <function>poll</function></funcdef> - <paramdef>struct pollfd *<parameter>ufds</parameter></paramdef> - <paramdef>unsigned int <parameter>nfds</parameter></paramdef> - <paramdef>int <parameter>timeout</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para> - Note: this documents the proposed CEC API. This API is not yet finalized and - is currently only available as a staging kernel module. - </para> - - <para>With the <function>poll()</function> function applications -can wait for CEC events.</para> - - <para>On success <function>poll()</function> returns the number of -file descriptors that have been selected (that is, file descriptors -for which the <structfield>revents</structfield> field of the -respective <structname>pollfd</structname> structure is non-zero). -CEC devices set the <constant>POLLIN</constant> and -<constant>POLLRDNORM</constant> flags in the -<structfield>revents</structfield> field if there are messages in the -receive queue. If the transmit queue has room for new messages, the -<constant>POLLOUT</constant> and <constant>POLLWRNORM</constant> -flags are set. If there are events in the event queue, then the -<constant>POLLPRI</constant> flag is set. -When the function timed out it returns a value of zero, on -failure it returns <returnvalue>-1</returnvalue> and the -<varname>errno</varname> variable is set appropriately. -</para> - - <para>For more details see the -<function>poll()</function> manual page.</para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para>On success, <function>poll()</function> returns the number -structures which have non-zero <structfield>revents</structfield> -fields, or zero if the call timed out. On error -<returnvalue>-1</returnvalue> is returned, and the -<varname>errno</varname> variable is set appropriately:</para> - - <variablelist> - <varlistentry> - <term><errorcode>EBADF</errorcode></term> - <listitem> - <para>One or more of the <parameter>ufds</parameter> members -specify an invalid file descriptor.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EFAULT</errorcode></term> - <listitem> - <para><parameter>ufds</parameter> references an inaccessible -memory area.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EINTR</errorcode></term> - <listitem> - <para>The call was interrupted by a signal.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The <parameter>nfds</parameter> argument is greater -than <constant>OPEN_MAX</constant>.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> |