| .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later | |
| .. c:namespace:: DTV.fe | |
| .. _FE_READ_SNR: | |
| *********** | |
| FE_READ_SNR | |
| *********** | |
| Name | |
| ==== | |
| FE_READ_SNR | |
| .. attention:: This ioctl is deprecated. | |
| Synopsis | |
| ======== | |
| .. c:macro:: FE_READ_SNR | |
| ``int ioctl(int fd, FE_READ_SNR, int16_t *snr)`` | |
| Arguments | |
| ========= | |
| ``fd`` | |
| File descriptor returned by :c:func:`open()`. | |
| ``snr`` | |
| The signal-to-noise ratio is stored into \*snr. | |
| Description | |
| =========== | |
| 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. | |
| Return Value | |
| ============ | |
| 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. |