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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-open:
+
+************
+media open()
+************
+
+Name
+====
+
+media-open - Open a media device
+
+
+Synopsis
+========
+
+.. code-block:: c
+
+    #include <fcntl.h>
+
+
+.. c:function:: int open( const char *device_name, int flags )
+    :name: mc-open
+
+Arguments
+=========
+
+``device_name``
+    Device to be opened.
+
+``flags``
+    Open flags. Access mode must be either ``O_RDONLY`` or ``O_RDWR``.
+    Other flags have no effect.
+
+
+Description
+===========
+
+To open a media device applications call :ref:`open() <media-func-open>` with the
+desired device name. The function has no side effects; the device
+configuration remain unchanged.
+
+When the device is opened in read-only mode, attempts to modify its
+configuration will result in an error, and ``errno`` will be set to
+EBADF.
+
+
+Return Value
+============
+
+:ref:`open() <func-open>` returns the new file descriptor on success. On error,
+-1 is returned, and ``errno`` is set appropriately. Possible error codes
+are:
+
+EACCES
+    The requested access to the file is not allowed.
+
+EMFILE
+    The process already has the maximum number of files open.
+
+ENFILE
+    The system limit on the total number of open files has been reached.
+
+ENOMEM
+    Insufficient kernel memory was available.
+
+ENXIO
+    No device corresponding to this device special file exists.