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+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _media-func-ioctl:
+
+*************
+media ioctl()
+*************
+
+Name
+====
+
+media-ioctl - Control a media device
+
+
+Synopsis
+========
+
+.. code-block:: c
+
+    #include <sys/ioctl.h>
+
+
+.. c:function:: int ioctl( int fd, int request, void *argp )
+    :name: mc-ioctl
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :c:func:`open() <mc-open>`.
+
+``request``
+    Media ioctl request code as defined in the media.h header file, for
+    example MEDIA_IOC_SETUP_LINK.
+
+``argp``
+    Pointer to a request-specific structure.
+
+
+Description
+===========
+
+The :ref:`ioctl() <media-func-ioctl>` function manipulates media device
+parameters. The argument ``fd`` must be an open file descriptor.
+
+The ioctl ``request`` code specifies the media function to be called. It
+has encoded in it whether the argument is an input, output or read/write
+parameter, and the size of the argument ``argp`` in bytes.
+
+Macros and structures definitions specifying media ioctl requests and
+their parameters are located in the media.h header file. All media ioctl
+requests, their respective function and parameters are specified in
+:ref:`media-user-func`.
+
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+Request-specific error codes are listed in the individual requests
+descriptions.
+
+When an ioctl that takes an output or read/write parameter fails, the
+parameter remains unmodified.