1*4882a593Smuzhiyun.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2*4882a593Smuzhiyun.. c:namespace:: DTV.fe 3*4882a593Smuzhiyun 4*4882a593Smuzhiyun.. _FE_READ_SNR: 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun*********** 7*4882a593SmuzhiyunFE_READ_SNR 8*4882a593Smuzhiyun*********** 9*4882a593Smuzhiyun 10*4882a593SmuzhiyunName 11*4882a593Smuzhiyun==== 12*4882a593Smuzhiyun 13*4882a593SmuzhiyunFE_READ_SNR 14*4882a593Smuzhiyun 15*4882a593Smuzhiyun.. attention:: This ioctl is deprecated. 16*4882a593Smuzhiyun 17*4882a593SmuzhiyunSynopsis 18*4882a593Smuzhiyun======== 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun.. c:macro:: FE_READ_SNR 21*4882a593Smuzhiyun 22*4882a593Smuzhiyun``int ioctl(int fd, FE_READ_SNR, int16_t *snr)`` 23*4882a593Smuzhiyun 24*4882a593SmuzhiyunArguments 25*4882a593Smuzhiyun========= 26*4882a593Smuzhiyun 27*4882a593Smuzhiyun``fd`` 28*4882a593Smuzhiyun File descriptor returned by :c:func:`open()`. 29*4882a593Smuzhiyun 30*4882a593Smuzhiyun``snr`` 31*4882a593Smuzhiyun The signal-to-noise ratio is stored into \*snr. 32*4882a593Smuzhiyun 33*4882a593SmuzhiyunDescription 34*4882a593Smuzhiyun=========== 35*4882a593Smuzhiyun 36*4882a593SmuzhiyunThis ioctl call returns the signal-to-noise ratio for the signal 37*4882a593Smuzhiyuncurrently received by the front-end. For this command, read-only access 38*4882a593Smuzhiyunto the device is sufficient. 39*4882a593Smuzhiyun 40*4882a593SmuzhiyunReturn Value 41*4882a593Smuzhiyun============ 42*4882a593Smuzhiyun 43*4882a593SmuzhiyunOn success 0 is returned. 44*4882a593Smuzhiyun 45*4882a593SmuzhiyunOn error -1 is returned, and the ``errno`` variable is set 46*4882a593Smuzhiyunappropriately. 47*4882a593Smuzhiyun 48*4882a593SmuzhiyunGeneric error codes are described at the 49*4882a593Smuzhiyun:ref:`Generic Error Codes <gen-errors>` chapter. 50