mirror_ubuntu-kernels/Documentation/userspace-api/media/dvb/fe-read-status.rst
Mauro Carvalho Chehab 059b1c5b15 media: docs: use the new SPDX header for GFDL-1.1 on *.rst files
SPDX v3.10 gained support for GFDL-1.1 with no invariant sections:

	https://spdx.org/licenses/GFDL-1.1-no-invariants-or-later.html

So, remove the license text, replacing them by this new SPDX
license.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-01 14:13:30 +02:00

66 lines
1.4 KiB
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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. _FE_READ_STATUS:
********************
ioctl FE_READ_STATUS
********************
Name
====
FE_READ_STATUS - Returns status information about the front-end. This call only requires - read-only access to the device
Synopsis
========
.. c:function:: int ioctl( int fd, FE_READ_STATUS, unsigned int *status )
:name: FE_READ_STATUS
Arguments
=========
``fd``
File descriptor returned by :ref:`open() <frontend_f_open>`.
``status``
pointer to a bitmask integer filled with the values defined by enum
:c:type:`fe_status`.
Description
===========
All Digital TV frontend devices support the ``FE_READ_STATUS`` ioctl. It is
used to check about the locking status of the frontend after being
tuned. The ioctl takes a pointer to an integer where the status will be
written.
.. note::
The size of status is actually sizeof(enum fe_status), with
varies according with the architecture. This needs to be fixed in the
future.
int fe_status
=============
The fe_status parameter is used to indicate the current state and/or
state changes of the frontend hardware. It is produced using the enum
:c:type:`fe_status` values on a bitmask
Return Value
============
On success 0 is returned.
On error -1 is returned, and the ``errno`` variable is set
appropriately.
Generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.