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+.. -*- 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
+
+
+ - .. row 1
+
+ - int fd
+
+ - File descriptor returned by a previous call to open().
+
+ - .. row 2
+
+ - int request
+
+ - Equals :ref:`FE_READ_SNR` for this command.
+
+ - .. row 3
+
+ - 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.