linux/Documentation/media/uapi/dvb/dmx-fwrite.rst
Mauro Carvalho Chehab cf8076c314 [media] docs-rst: Convert DVB uAPI to use C function references
Name all ioctl references and make them match the ioctls that
are documented. That will improve the cross-reference index,
as it will have all ioctls and syscalls there.

While here, improve the documentation, marking the deprecated
ioctls, and making the non-deprecated ones more like the rest
of the media book.

Also, add a notice for ioctls that still require documentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-22 21:23:34 -03:00

76 lines
1.6 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _dmx_fwrite:
=================
DVB demux write()
=================
Name
----
DVB demux write()
Synopsis
--------
.. c:function:: ssize_t write(int fd, const void *buf, size_t count)
:name: dvb-dmx-write
Arguments
---------
``fd``
File descriptor returned by a previous call to :c:func:`open() <dvb-ca-open>`.
``buf``
Buffer with data to be written
``count``
Number of bytes at the buffer
Description
-----------
This system call is only provided by the logical device
/dev/dvb/adapter0/dvr0, associated with the physical demux device that
provides the actual DVR functionality. It is used for replay of a
digitally recorded Transport Stream. Matching filters have to be defined
in the corresponding physical demux device, /dev/dvb/adapter0/demux0.
The amount of data to be transferred is implied by count.
Return Value
------------
.. tabularcolumns:: |p{2.5cm}|p{15.0cm}|
.. flat-table::
:header-rows: 0
:stub-columns: 0
- .. row 1
- ``EWOULDBLOCK``
- No data was written. This might happen if O_NONBLOCK was
specified and there is no more buffer space available (if
O_NONBLOCK is not specified the function will block until buffer
space is available).
- .. row 2
- ``EBUSY``
- This error code indicates that there are conflicting requests. The
corresponding demux device is setup to receive data from the
front- end. Make sure that these filters are stopped and that the
filters with input set to DMX_IN_DVR are started.
- .. row 3
- ``EBADF``
- fd is not a valid open file descriptor.