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/userspace-api/media/fdl-appendix.rst.
7..
8.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
9
10.. _FE_READ_SNR:
11
12***********
13FE_READ_SNR
14***********
15
16Name
17====
18
19FE_READ_SNR
20
21.. attention:: This ioctl is deprecated.
22
23Synopsis
24========
25
26.. c:function:: int  ioctl(int fd, FE_READ_SNR, int16_t *snr)
27    :name: FE_READ_SNR
28
29
30Arguments
31=========
32
33``fd``
34    File descriptor returned by :c:func:`open() <dvb-fe-open>`.
35
36``snr``
37    The signal-to-noise ratio is stored into \*snr.
38
39
40Description
41===========
42
43This ioctl call returns the signal-to-noise ratio for the signal
44currently received by the front-end. For this command, read-only access
45to the device is sufficient.
46
47
48Return Value
49============
50
51On success 0 is returned.
52
53On error -1 is returned, and the ``errno`` variable is set
54appropriately.
55
56Generic error codes are described at the
57:ref:`Generic Error Codes <gen-errors>` chapter.
58