| .. -*- coding: utf-8; mode: rst -*- |
| |
| .. _FE_READ_SNR: |
| |
| *********** |
| FE_READ_SNR |
| *********** |
| |
| Name |
| ==== |
| |
| FE_READ_SNR |
| |
| |
| Synopsis |
| ======== |
| |
| .. cpp:function:: int ioctl(int fd, int request = FE_READ_SNR, int16_t *snr) |
| |
| |
| Arguments |
| ========= |
| |
| .. flat-table:: |
| :header-rows: 0 |
| :stub-columns: 0 |
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| |
| - .. row 1 |
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| - int fd |
| |
| - File descriptor returned by a previous call to open(). |
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| - .. row 2 |
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| - int request |
| |
| - Equals :ref:`FE_READ_SNR` for this command. |
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| - .. row 3 |
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| - uint16_t \*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 and the ``errno`` variable is set |
| appropriately. The generic error codes are described at the |
| :ref:`Generic Error Codes <gen-errors>` chapter. |