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 | ||
| 9 | DESCRIPTION | |
| 10 | ||
| 11 | This ioctl call returns the signal-to-noise ratio for the signal | |
| 12 | currently received by the front-end. For this command, read-only access | |
| 13 | to the device is sufficient. | |
| 14 | ||
| 15 | SYNOPSIS | |
| 16 | ||
| 7347081e | 17 | int ioctl(int fd, int request = :ref:`FE_READ_SNR`, |
| 5377d91f MH |
18 | uint16_t *snr); |
| 19 | ||
| 20 | PARAMETERS | |
| 21 | ||
| 22 | ||
| 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 | ||
| 43 | - uint16_t *snr | |
| 44 | ||
| 45 | - The signal-to-noise ratio is stored into *snr. | |
| 46 | ||
| 47 | ||
| 48 | RETURN VALUE | |
| 49 | ||
| 50 | On success 0 is returned, on error -1 and the ``errno`` variable is set | |
| 51 | appropriately. The generic error codes are described at the | |
| 52 | :ref:`Generic Error Codes <gen-errors>` chapter. | |
| 53 | ||
| 54 | ||
| 55 | .. ------------------------------------------------------------------------------ | |
| 56 | .. This file was automatically converted from DocBook-XML with the dbxml | |
| 57 | .. library (https://github.com/return42/sphkerneldoc). The origin XML comes | |
| 58 | .. from the linux kernel, refer to: | |
| 59 | .. | |
| 60 | .. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook | |
| 61 | .. ------------------------------------------------------------------------------ |