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Linux kernel mirror (for testing)
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1.. Permission is granted to copy, distribute and/or modify this
2.. document under the terms of the GNU Free Documentation License,
3.. Version 1.1 or any later version published by the Free Software
4.. Foundation, with no Invariant Sections, no Front-Cover Texts
5.. and no Back-Cover Texts. A copy of the license is included at
6.. Documentation/media/uapi/fdl-appendix.rst.
7..
8.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
9
10.. _VIDEO_COMMAND:
11
12=============
13VIDEO_COMMAND
14=============
15
16Name
17----
18
19VIDEO_COMMAND
20
21.. attention:: This ioctl is deprecated.
22
23Synopsis
24--------
25
26.. c:function:: int ioctl(int fd, VIDEO_COMMAND, struct video_command *cmd)
27 :name: VIDEO_COMMAND
28
29
30Arguments
31---------
32
33.. flat-table::
34 :header-rows: 0
35 :stub-columns: 0
36
37
38 - .. row 1
39
40 - int fd
41
42 - File descriptor returned by a previous call to open().
43
44 - .. row 2
45
46 - int request
47
48 - Equals VIDEO_COMMAND for this command.
49
50 - .. row 3
51
52 - struct video_command \*cmd
53
54 - Commands the decoder.
55
56
57Description
58-----------
59
60This ioctl is obsolete. Do not use in new drivers. For V4L2 decoders
61this ioctl has been replaced by the
62:ref:`VIDIOC_DECODER_CMD` ioctl.
63
64This ioctl commands the decoder. The ``video_command`` struct is a
65subset of the ``v4l2_decoder_cmd`` struct, so refer to the
66:ref:`VIDIOC_DECODER_CMD` documentation for
67more information.
68
69.. c:type:: struct video_command
70
71.. code-block:: c
72
73 /* The structure must be zeroed before use by the application
74 This ensures it can be extended safely in the future. */
75 struct video_command {
76 __u32 cmd;
77 __u32 flags;
78 union {
79 struct {
80 __u64 pts;
81 } stop;
82
83 struct {
84 /* 0 or 1000 specifies normal speed,
85 1 specifies forward single stepping,
86 -1 specifies backward single stepping,
87 >1: playback at speed/1000 of the normal speed,
88 <-1: reverse playback at (-speed/1000) of the normal speed. */
89 __s32 speed;
90 __u32 format;
91 } play;
92
93 struct {
94 __u32 data[16];
95 } raw;
96 };
97 };
98
99
100Return Value
101------------
102
103On success 0 is returned, on error -1 and the ``errno`` variable is set
104appropriately. The generic error codes are described at the
105:ref:`Generic Error Codes <gen-errors>` chapter.