Function lfind 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn lfind(
    key: *const c_void,
    base: *const c_void,
    nelp: *mut usize,
    width: usize,
    compar: Option<unsafe extern "C" fn(*const c_void, *const c_void) -> c_int>,
) -> *mut c_void