Function ReadMagnitude 

pub unsafe extern "C" fn ReadMagnitude(
    mag: *mut *mut f32,
    infiles: *mut infileT,
    linelen: c_long,
    nlines: c_long,
    tileparams: *mut tileparamT,
) -> c_int

Reads the interferogram magnitude in the specfied file if it exists. Memory for the magnitude array should already have been allocated by ReadInputFile().