aboutsummaryrefslogtreecommitdiff
path: root/Documentation/media/uapi/dvb/video-fopen.rst
blob: 203a2c56f10a601f4a4b3a139caa4f922c3a8377 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
.. -*- coding: utf-8; mode: rst -*-

.. _video_fopen:

================
dvb video open()
================

Name
----

dvb video open()

.. attention:: This ioctl is deprecated.

Synopsis
--------

.. c:function:: int open(const char *deviceName, int flags)


Arguments
---------

.. flat-table::
    :header-rows:  0
    :stub-columns: 0


    -  .. row 1

       -  const char \*deviceName

       -  Name of specific video device.

    -  .. row 2

       -  int flags

       -  A bit-wise OR of the following flags:

    -  .. row 3

       -
       -  O_RDONLY read-only access

    -  .. row 4

       -
       -  O_RDWR read/write access

    -  .. row 5

       -
       -  O_NONBLOCK open in non-blocking mode

    -  .. row 6

       -
       -  (blocking mode is the default)


Description
-----------

This system call opens a named video device (e.g.
/dev/dvb/adapter0/video0) for subsequent use.

When an open() call has succeeded, the device will be ready for use. The
significance of blocking or non-blocking mode is described in the
documentation for functions where there is a difference. It does not
affect the semantics of the open() call itself. A device opened in
blocking mode can later be put into non-blocking mode (and vice versa)
using the F_SETFL command of the fcntl system call. This is a standard
system call, documented in the Linux manual page for fcntl. Only one
user can open the Video Device in O_RDWR mode. All other attempts to
open the device in this mode will fail, and an error-code will be
returned. If the Video Device is opened in O_RDONLY mode, the only
ioctl call that can be used is VIDEO_GET_STATUS. All other call will
return an error code.


Return Value
------------

.. tabularcolumns:: |p{2.5cm}|p{15.0cm}|

.. flat-table::
    :header-rows:  0
    :stub-columns: 0


    -  .. row 1

       -  ``ENODEV``

       -  Device driver not loaded/available.

    -  .. row 2

       -  ``EINTERNAL``

       -  Internal error.

    -  .. row 3

       -  ``EBUSY``

       -  Device or resource busy.

    -  .. row 4

       -  ``EINVAL``

       -  Invalid argument.