Function SoapySDRDevice_getHardwareTime 

pub unsafe extern "C" fn SoapySDRDevice_getHardwareTime(
    device: *const SoapySDRDevice,
    what: *const c_char,
) -> c_longlong

Read the time from the hardware clock on the device.

The what argument can refer to a specific time counter. \param device a pointer to a device instance \param what optional argument \return the time in nanoseconds