OpenCloudOS-Kernel/Documentation/userspace-api/media/dvb/video-command.rst

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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. c:namespace:: DTV.video
.. _VIDEO_COMMAND:
=============
VIDEO_COMMAND
=============
Name
----
VIDEO_COMMAND
.. attention:: This ioctl is deprecated.
Synopsis
--------
.. c:macro:: VIDEO_COMMAND
``int ioctl(int fd, VIDEO_COMMAND, struct video_command *cmd)``
Arguments
---------
.. flat-table::
:header-rows: 0
:stub-columns: 0
- .. row 1
- int fd
- File descriptor returned by a previous call to open().
- .. row 2
- int request
- Equals VIDEO_COMMAND for this command.
- .. row 3
- struct video_command \*cmd
- Commands the decoder.
Description
-----------
This ioctl is obsolete. Do not use in new drivers. For V4L2 decoders
this ioctl has been replaced by the
:ref:`VIDIOC_DECODER_CMD` ioctl.
This ioctl commands the decoder. The ``video_command`` struct is a
subset of the ``v4l2_decoder_cmd`` struct, so refer to the
:ref:`VIDIOC_DECODER_CMD` documentation for
more information.
.. c:type:: video_command
.. code-block:: c
/* The structure must be zeroed before use by the application
This ensures it can be extended safely in the future. */
struct video_command {
__u32 cmd;
__u32 flags;
union {
struct {
__u64 pts;
} stop;
struct {
/* 0 or 1000 specifies normal speed,
1 specifies forward single stepping,
-1 specifies backward single stepping,
>1: playback at speed/1000 of the normal speed,
<-1: reverse playback at (-speed/1000) of the normal speed. */
__s32 speed;
__u32 format;
} play;
struct {
__u32 data[16];
} raw;
};
};
Return Value
------------
On success 0 is returned, on error -1 and the ``errno`` variable is set
appropriately. The generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.