pub extern "C" fn setsockopt(
fn_ptr: Option<&extern "C" fn(_: c_int, _: c_int, _: c_int, _: *const c_void, _: socklen_t) -> c_int>,
socket: c_int,
level: c_int,
name: c_int,
value: *const c_void,
option_len: socklen_t,
) -> c_int