Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 1 | .. -*- coding: utf-8; mode: rst -*- |
| 2 | |
| 3 | .. _cec-func-open: |
| 4 | |
| 5 | ********** |
| 6 | cec open() |
| 7 | ********** |
| 8 | |
Markus Heiser | 21c6269 | 2016-07-08 20:55:43 +0200 | [diff] [blame] | 9 | Name |
| 10 | ==== |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 11 | |
Markus Heiser | 21c6269 | 2016-07-08 20:55:43 +0200 | [diff] [blame] | 12 | cec-open - Open a cec device |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 13 | |
| 14 | Synopsis |
| 15 | ======== |
| 16 | |
| 17 | .. code-block:: c |
| 18 | |
| 19 | #include <fcntl.h> |
| 20 | |
| 21 | |
Markus Heiser | 21c6269 | 2016-07-08 20:55:43 +0200 | [diff] [blame] | 22 | .. cpp:function:: int open( const char *device_name, int flags ) |
| 23 | |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 24 | |
| 25 | Arguments |
| 26 | ========= |
| 27 | |
| 28 | ``device_name`` |
| 29 | Device to be opened. |
| 30 | |
| 31 | ``flags`` |
| 32 | Open flags. Access mode must be ``O_RDWR``. |
| 33 | |
| 34 | When the ``O_NONBLOCK`` flag is given, the |
Hans Verkuil | e5208ed | 2016-07-19 06:26:13 -0300 | [diff] [blame^] | 35 | :ref:`CEC_RECEIVE <CEC_RECEIVE>` and :ref:`CEC_DQEVENT <CEC_DQEVENT>` ioctls |
| 36 | will return the ``EAGAIN`` error code when no message or event is available, and |
| 37 | ioctls :ref:`CEC_TRANSMIT <CEC_TRANSMIT>`, |
Hans Verkuil | 1267c60 | 2016-07-13 08:48:54 -0300 | [diff] [blame] | 38 | :ref:`CEC_ADAP_S_PHYS_ADDR <CEC_ADAP_S_PHYS_ADDR>` and |
| 39 | :ref:`CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>` |
Hans Verkuil | e5208ed | 2016-07-19 06:26:13 -0300 | [diff] [blame^] | 40 | all return 0. |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 41 | |
| 42 | Other flags have no effect. |
| 43 | |
| 44 | |
| 45 | Description |
| 46 | =========== |
| 47 | |
Mauro Carvalho Chehab | 706f8a9 | 2016-07-10 11:57:43 -0300 | [diff] [blame] | 48 | .. note:: This documents the proposed CEC API. This API is not yet finalized |
| 49 | and is currently only available as a staging kernel module. |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 50 | |
| 51 | To open a cec device applications call :c:func:`open()` with the |
| 52 | desired device name. The function has no side effects; the device |
| 53 | configuration remain unchanged. |
| 54 | |
| 55 | When the device is opened in read-only mode, attempts to modify its |
| 56 | configuration will result in an error, and ``errno`` will be set to |
| 57 | EBADF. |
| 58 | |
| 59 | |
| 60 | Return Value |
| 61 | ============ |
| 62 | |
| 63 | :c:func:`open()` returns the new file descriptor on success. On error, |
| 64 | -1 is returned, and ``errno`` is set appropriately. Possible error codes |
| 65 | include: |
| 66 | |
Mauro Carvalho Chehab | b2a5843 | 2016-07-08 17:59:27 -0300 | [diff] [blame] | 67 | ``EACCES`` |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 68 | The requested access to the file is not allowed. |
| 69 | |
Mauro Carvalho Chehab | b2a5843 | 2016-07-08 17:59:27 -0300 | [diff] [blame] | 70 | ``EMFILE`` |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 71 | The process already has the maximum number of files open. |
| 72 | |
Mauro Carvalho Chehab | b2a5843 | 2016-07-08 17:59:27 -0300 | [diff] [blame] | 73 | ``ENFILE`` |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 74 | The system limit on the total number of open files has been reached. |
| 75 | |
Mauro Carvalho Chehab | b2a5843 | 2016-07-08 17:59:27 -0300 | [diff] [blame] | 76 | ``ENOMEM`` |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 77 | Insufficient kernel memory was available. |
| 78 | |
Mauro Carvalho Chehab | b2a5843 | 2016-07-08 17:59:27 -0300 | [diff] [blame] | 79 | ``ENXIO`` |
Markus Heiser | e2460b1 | 2016-07-08 20:55:42 +0200 | [diff] [blame] | 80 | No device corresponding to this device special file exists. |