| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 1 | .. -*- coding: utf-8; mode: rst -*- |
| 2 | |
| 3 | .. _FE_READ_SNR: |
| 4 | |
| 5 | *********** |
| 6 | FE_READ_SNR |
| 7 | *********** |
| 8 | |
| Mauro Carvalho Chehab | 15e7d61 | 2016-07-05 15:14:35 -0300 | [diff] [blame] | 9 | Name |
| Mauro Carvalho Chehab | 586027c | 2016-07-05 07:58:48 -0300 | [diff] [blame] | 10 | ==== |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 11 | |
| Mauro Carvalho Chehab | 586027c | 2016-07-05 07:58:48 -0300 | [diff] [blame] | 12 | FE_READ_SNR |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 13 | |
| Mauro Carvalho Chehab | cf8076c | 2016-08-19 16:56:15 -0300 | [diff] [blame] | 14 | .. attention:: This ioctl is deprecated. |
| Mauro Carvalho Chehab | 15e7d61 | 2016-07-05 15:14:35 -0300 | [diff] [blame] | 15 | |
| 16 | Synopsis |
| Mauro Carvalho Chehab | 586027c | 2016-07-05 07:58:48 -0300 | [diff] [blame] | 17 | ======== |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 18 | |
| Mauro Carvalho Chehab | cf8076c | 2016-08-19 16:56:15 -0300 | [diff] [blame] | 19 | .. c:function:: int ioctl(int fd, FE_READ_SNR, int16_t *snr) |
| 20 | :name: FE_READ_SNR |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 21 | |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 22 | |
| Mauro Carvalho Chehab | 15e7d61 | 2016-07-05 15:14:35 -0300 | [diff] [blame] | 23 | Arguments |
| Mauro Carvalho Chehab | 586027c | 2016-07-05 07:58:48 -0300 | [diff] [blame] | 24 | ========= |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 25 | |
| Mauro Carvalho Chehab | cf8076c | 2016-08-19 16:56:15 -0300 | [diff] [blame] | 26 | ``fd`` |
| 27 | File descriptor returned by :c:func:`open() <dvb-fe-open>`. |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 28 | |
| Mauro Carvalho Chehab | cf8076c | 2016-08-19 16:56:15 -0300 | [diff] [blame] | 29 | ``snr`` |
| 30 | The signal-to-noise ratio is stored into \*snr. |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 31 | |
| 32 | |
| Mauro Carvalho Chehab | 15e7d61 | 2016-07-05 15:14:35 -0300 | [diff] [blame] | 33 | Description |
| Mauro Carvalho Chehab | 586027c | 2016-07-05 07:58:48 -0300 | [diff] [blame] | 34 | =========== |
| 35 | |
| 36 | This ioctl call returns the signal-to-noise ratio for the signal |
| 37 | currently received by the front-end. For this command, read-only access |
| 38 | to the device is sufficient. |
| 39 | |
| 40 | |
| Mauro Carvalho Chehab | 15e7d61 | 2016-07-05 15:14:35 -0300 | [diff] [blame] | 41 | Return Value |
| Mauro Carvalho Chehab | 586027c | 2016-07-05 07:58:48 -0300 | [diff] [blame] | 42 | ============ |
| Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 43 | |
| 44 | On success 0 is returned, on error -1 and the ``errno`` variable is set |
| 45 | appropriately. The generic error codes are described at the |
| 46 | :ref:`Generic Error Codes <gen-errors>` chapter. |