media-func-open.rst (1339B)
1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2.. c:namespace:: MC 3 4.. _media-func-open: 5 6************ 7media open() 8************ 9 10Name 11==== 12 13media-open - Open a media device 14 15Synopsis 16======== 17 18.. code-block:: c 19 20 #include <fcntl.h> 21 22.. c:function:: int open( const char *device_name, int flags ) 23 24Arguments 25========= 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 34Description 35=========== 36 37To open a media device applications call :c:func:`open()` with the 38desired device name. The function has no side effects; the device 39configuration remain unchanged. 40 41When the device is opened in read-only mode, attempts to modify its 42configuration will result in an error, and ``errno`` will be set to 43EBADF. 44 45Return Value 46============ 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 codes 50are: 51 52EACCES 53 The requested access to the file is not allowed. 54 55EMFILE 56 The process already has the maximum number of files open. 57 58ENFILE 59 The system limit on the total number of open files has been reached. 60 61ENOMEM 62 Insufficient kernel memory was available. 63 64ENXIO 65 No device corresponding to this device special file exists.