projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 5377d91f MH |
1 | .. -*- coding: utf-8; mode: rst -*- |
| 2 | ||
| 3 | .. _FE_READ_SNR: | |
| 4 | ||
| 5 | *********** | |
| 6 | FE_READ_SNR | |
| 7 | *********** | |
| 8 | ||
| 15e7d615 | 9 | Name |
| 586027ce | 10 | ==== |
| 5377d91f | 11 | |
| 586027ce | 12 | FE_READ_SNR |
| 5377d91f | 13 | |
| 15e7d615 MCC |
14 | |
| 15 | Synopsis | |
| 586027ce | 16 | ======== |
| 5377d91f | 17 | |
| 5929cb17 | 18 | .. cpp:function:: int ioctl(int fd, int request = FE_READ_SNR, int16_t *snr) |
| 5377d91f | 19 | |
| 5377d91f | 20 | |
| 15e7d615 | 21 | Arguments |
| 586027ce | 22 | ========= |
| 5377d91f MH |
23 | |
| 24 | .. flat-table:: | |
| 25 | :header-rows: 0 | |
| 26 | :stub-columns: 0 | |
| 27 | ||
| 28 | ||
| 29 | - .. row 1 | |
| 30 | ||
| 31 | - int fd | |
| 32 | ||
| 33 | - File descriptor returned by a previous call to open(). | |
| 34 | ||
| 35 | - .. row 2 | |
| 36 | ||
| 37 | - int request | |
| 38 | ||
| 7347081e | 39 | - Equals :ref:`FE_READ_SNR` for this command. |
| 5377d91f MH |
40 | |
| 41 | - .. row 3 | |
| 42 | ||
| 6fcf645e | 43 | - uint16_t \*snr |
| 5377d91f | 44 | |
| 6fcf645e | 45 | - The signal-to-noise ratio is stored into \*snr. |
| 5377d91f MH |
46 | |
| 47 | ||
| 15e7d615 | 48 | Description |
| 586027ce MCC |
49 | =========== |
| 50 | ||
| 51 | This ioctl call returns the signal-to-noise ratio for the signal | |
| 52 | currently received by the front-end. For this command, read-only access | |
| 53 | to the device is sufficient. | |
| 54 | ||
| 55 | ||
| 15e7d615 | 56 | Return Value |
| 586027ce | 57 | ============ |
| 5377d91f MH |
58 | |
| 59 | On success 0 is returned, on error -1 and the ``errno`` variable is set | |
| 60 | appropriately. The generic error codes are described at the | |
| 61 | :ref:`Generic Error Codes <gen-errors>` chapter. |