|  | .. 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. |