Function SoapySDRDevice_getSampleRate 

pub unsafe extern "C" fn SoapySDRDevice_getSampleRate(
    device: *const SoapySDRDevice,
    direction: c_int,
    channel: usize,
) -> f64

Get the baseband sample rate of the chain.

\param device a pointer to a device instance \param direction the channel direction RX or TX \param channel an available channel on the device \return the sample rate in samples per second