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Diffstat (limited to 'Documentation/linux_tv/media/dvb/FE_READ_SNR.rst')
-rw-r--r-- | Documentation/linux_tv/media/dvb/FE_READ_SNR.rst | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/Documentation/linux_tv/media/dvb/FE_READ_SNR.rst b/Documentation/linux_tv/media/dvb/FE_READ_SNR.rst new file mode 100644 index 0000000..b8a6397 --- /dev/null +++ b/Documentation/linux_tv/media/dvb/FE_READ_SNR.rst @@ -0,0 +1,61 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _FE_READ_SNR: + +*********** +FE_READ_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. + +SYNOPSIS + +int ioctl(int fd, int request = :ref:`FE_READ_SNR <FE_READ_SNR>`, +uint16_t *snr); + +PARAMETERS + + + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + + - .. row 1 + + - int fd + + - File descriptor returned by a previous call to open(). + + - .. row 2 + + - int request + + - Equals :ref:`FE_READ_SNR <FE_READ_SNR>` for this command. + + - .. row 3 + + - uint16_t *snr + + - The signal-to-noise ratio is stored into *snr. + + +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. + + +.. ------------------------------------------------------------------------------ +.. This file was automatically converted from DocBook-XML with the dbxml +.. library (https://github.com/return42/sphkerneldoc). The origin XML comes +.. from the linux kernel, refer to: +.. +.. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook +.. ------------------------------------------------------------------------------ |