1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2 3.. _cec-func-open: 4 5********** 6cec open() 7********** 8 9Name 10==== 11 12cec-open - Open a cec device 13 14Synopsis 15======== 16 17.. code-block:: c 18 19 #include <fcntl.h> 20 21 22.. c:function:: int open( const char *device_name, int flags ) 23 :name: cec-open 24 25 26Arguments 27========= 28 29``device_name`` 30 Device to be opened. 31 32``flags`` 33 Open flags. Access mode must be ``O_RDWR``. 34 35 When the ``O_NONBLOCK`` flag is given, the 36 :ref:`CEC_RECEIVE <CEC_RECEIVE>` and :ref:`CEC_DQEVENT <CEC_DQEVENT>` ioctls 37 will return the ``EAGAIN`` error code when no message or event is available, and 38 ioctls :ref:`CEC_TRANSMIT <CEC_TRANSMIT>`, 39 :ref:`CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>` and 40 :ref:`CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>` 41 all return 0. 42 43 Other flags have no effect. 44 45 46Description 47=========== 48 49To open a cec device applications call :c:func:`open() <cec-open>` with the 50desired device name. The function has no side effects; the device 51configuration remain unchanged. 52 53When the device is opened in read-only mode, attempts to modify its 54configuration will result in an error, and ``errno`` will be set to 55EBADF. 56 57 58Return Value 59============ 60 61:c:func:`open() <cec-open>` returns the new file descriptor on success. On error, 62-1 is returned, and ``errno`` is set appropriately. Possible error codes 63include: 64 65``EACCES`` 66 The requested access to the file is not allowed. 67 68``EMFILE`` 69 The process already has the maximum number of files open. 70 71``ENFILE`` 72 The system limit on the total number of open files has been reached. 73 74``ENOMEM`` 75 Insufficient kernel memory was available. 76 77``ENXIO`` 78 No device corresponding to this device special file exists. 79