fe-read-snr.rst (852B)
1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2.. c:namespace:: DTV.fe 3 4.. _FE_READ_SNR: 5 6*********** 7FE_READ_SNR 8*********** 9 10Name 11==== 12 13FE_READ_SNR 14 15.. attention:: This ioctl is deprecated. 16 17Synopsis 18======== 19 20.. c:macro:: FE_READ_SNR 21 22``int ioctl(int fd, FE_READ_SNR, int16_t *snr)`` 23 24Arguments 25========= 26 27``fd`` 28 File descriptor returned by :c:func:`open()`. 29 30``snr`` 31 The signal-to-noise ratio is stored into \*snr. 32 33Description 34=========== 35 36This ioctl call returns the signal-to-noise ratio for the signal 37currently received by the front-end. For this command, read-only access 38to the device is sufficient. 39 40Return Value 41============ 42 43On success 0 is returned. 44 45On error -1 is returned, and the ``errno`` variable is set 46appropriately. 47 48Generic error codes are described at the 49:ref:`Generic Error Codes <gen-errors>` chapter.