diff options
Diffstat (limited to 'Documentation/DocBook/v4l/func-ioctl.xml')
| -rw-r--r-- | Documentation/DocBook/v4l/func-ioctl.xml | 145 |
1 files changed, 0 insertions, 145 deletions
diff --git a/Documentation/DocBook/v4l/func-ioctl.xml b/Documentation/DocBook/v4l/func-ioctl.xml deleted file mode 100644 index b60fd37a6295..000000000000 --- a/Documentation/DocBook/v4l/func-ioctl.xml +++ /dev/null @@ -1,145 +0,0 @@ -<refentry id="func-ioctl"> - <refmeta> - <refentrytitle>V4L2 ioctl()</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>v4l2-ioctl</refname> - <refpurpose>Program a V4L2 device</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <sys/ioctl.h></funcsynopsisinfo> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>void *<parameter>argp</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Arguments</title> - - <variablelist> - <varlistentry> - <term><parameter>fd</parameter></term> - <listitem> - <para>&fd;</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>request</parameter></term> - <listitem> - <para>V4L2 ioctl request code as defined in the <filename>videodev2.h</filename> header file, for example -VIDIOC_QUERYCAP.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para>Pointer to a function parameter, usually a structure.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>The <function>ioctl()</function> function is used to program -V4L2 devices. The argument <parameter>fd</parameter> must be an open -file descriptor. An ioctl <parameter>request</parameter> has encoded -in it whether the argument is an input, output or read/write -parameter, and the size of the argument <parameter>argp</parameter> in -bytes. Macros and defines specifying V4L2 ioctl requests are located -in the <filename>videodev2.h</filename> header file. -Applications should use their own copy, not include the version in the -kernel sources on the system they compile on. All V4L2 ioctl requests, -their respective function and parameters are specified in <xref - linkend="user-func" />.</para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para>On success the <function>ioctl()</function> function returns -<returnvalue>0</returnvalue> and does not reset the -<varname>errno</varname> variable. On failure -<returnvalue>-1</returnvalue> is returned, when the ioctl takes an -output or read/write parameter it remains unmodified, and the -<varname>errno</varname> variable is set appropriately. See below for -possible error codes. Generic errors like <errorcode>EBADF</errorcode> -or <errorcode>EFAULT</errorcode> are not listed in the sections -discussing individual ioctl requests.</para> - <para>Note ioctls may return undefined error codes. Since errors -may have side effects such as a driver reset applications should -abort on unexpected errors.</para> - - <variablelist> - <varlistentry> - <term><errorcode>EBADF</errorcode></term> - <listitem> - <para><parameter>fd</parameter> is not a valid open file -descriptor.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EBUSY</errorcode></term> - <listitem> - <para>The property cannot be changed right now. Typically -this error code is returned when I/O is in progress or the driver -supports multiple opens and another process locked the property.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EFAULT</errorcode></term> - <listitem> - <para><parameter>argp</parameter> references an inaccessible -memory area.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>ENOTTY</errorcode></term> - <listitem> - <para><parameter>fd</parameter> is not associated with a -character special device.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The <parameter>request</parameter> or the data pointed -to by <parameter>argp</parameter> is not valid. This is a very common -error code, see the individual ioctl requests listed in <xref - linkend="user-func" /> for actual causes.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>ENOMEM</errorcode></term> - <listitem> - <para>Not enough physical or virtual memory was available to -complete the request.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>ERANGE</errorcode></term> - <listitem> - <para>The application attempted to set a control with the -&VIDIOC-S-CTRL; ioctl to a value which is out of bounds.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> - -<!-- -Local Variables: -mode: sgml -sgml-parent-document: "v4l2.sgml" -indent-tabs-mode: nil -End: ---> |