.. c:namespace:: DTV.fe
FE_READ_SNR
Attention!
This ioctl is deprecated.
.. c:macro:: FE_READ_SNR
int ioctl(int fd, FE_READ_SNR, int16_t *snr)
fd- File descriptor returned by :c:func:`open()`.
snr- The signal-to-noise ratio is stored into *snr.
This ioctl call returns the signal-to-noise ratio for the signal currently received by the front-end. For this command, read-only access to the device is sufficient.
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.