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