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1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later2.. c:namespace:: MC3 4.. _media-func-open:5 6************7media open()8************9 10Name11====12 13media-open - Open a media device14 15Synopsis16========17 18.. code-block:: c19 20 #include <fcntl.h>21 22.. c:function:: int open( const char *device_name, int flags )23 24Arguments25=========26 27``device_name``28 Device to be opened.29 30``flags``31 Open flags. Access mode must be either ``O_RDONLY`` or ``O_RDWR``.32 Other flags have no effect.33 34Description35===========36 37To open a media device applications call :c:func:`open()` with the38desired device name. The function has no side effects; the device39configuration remain unchanged.40 41When the device is opened in read-only mode, attempts to modify its42configuration will result in an error, and ``errno`` will be set to43EBADF.44 45Return Value46============47 48:c:func:`open()` returns the new file descriptor on success. On error,49-1 is returned, and ``errno`` is set appropriately. Possible error codes50are:51 52EACCES53 The requested access to the file is not allowed.54 55EMFILE56 The process already has the maximum number of files open.57 58ENFILE59 The system limit on the total number of open files has been reached.60 61ENOMEM62 Insufficient kernel memory was available.63 64ENXIO65 No device corresponding to this device special file exists.66