Function leptonica_sys::freadHeaderPng

pub unsafe extern "C" fn freadHeaderPng(
    fp: *mut FILE, 
    pw: *mut l_int32, 
    ph: *mut l_int32, 
    pbps: *mut l_int32, 
    pspp: *mut l_int32, 
    piscmap: *mut l_int32
) -> l_ok