1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2.. c:namespace:: DTV.fe
3
4.. _FE_GET_PROPERTY:
5
6**************************************
7ioctl FE_SET_PROPERTY, FE_GET_PROPERTY
8**************************************
9
10Name
11====
12
13FE_SET_PROPERTY - FE_GET_PROPERTY - FE_SET_PROPERTY sets one or more frontend properties. - FE_GET_PROPERTY returns one or more frontend properties.
14
15Synopsis
16========
17
18.. c:macro:: FE_GET_PROPERTY
19
20``int ioctl(int fd, FE_GET_PROPERTY, struct dtv_properties *argp)``
21
22.. c:macro:: FE_SET_PROPERTY
23
24``int ioctl(int fd, FE_SET_PROPERTY, struct dtv_properties *argp)``
25
26Arguments
27=========
28
29``fd``
30    File descriptor returned by :c:func:`open()`.
31
32``argp``
33    Pointer to struct :c:type:`dtv_properties`.
34
35Description
36===========
37
38All Digital TV frontend devices support the ``FE_SET_PROPERTY`` and
39``FE_GET_PROPERTY`` ioctls. The supported properties and statistics
40depends on the delivery system and on the device:
41
42-  ``FE_SET_PROPERTY:``
43
44   -  This ioctl is used to set one or more frontend properties.
45
46   -  This is the basic command to request the frontend to tune into
47      some frequency and to start decoding the digital TV signal.
48
49   -  This call requires read/write access to the device.
50
51.. note::
52
53   At return, the values aren't updated to reflect the actual
54   parameters used. If the actual parameters are needed, an explicit
55   call to ``FE_GET_PROPERTY`` is needed.
56
57-  ``FE_GET_PROPERTY:``
58
59   -  This ioctl is used to get properties and statistics from the
60      frontend.
61
62   -  No properties are changed, and statistics aren't reset.
63
64   -  This call only requires read-only access to the device.
65
66Return Value
67============
68
69On success 0 is returned.
70
71On error -1 is returned, and the ``errno`` variable is set
72appropriately.
73
74Generic error codes are described at the
75:ref:`Generic Error Codes <gen-errors>` chapter.
76