return err
	}
	return operr
}

func controlRawConn(c syscall.RawConn, addr Addr) error {
	var operr error
	fn := func(s uintptr) {
		var v, l int32
		l = int32(unsafe.Sizeof(v))
		operr = syscall.Getsockopt(syscall.Handle(s), syscall.SOL_SOCKET, syscall.SO_REUSEADDR, (*byte)(unsafe.Pointer(&v)), &l)
		if operr != nil {
			return
		}
		switch addr := addr.(type) {
		case *TCPAddr:

			default:
			}
			return nil, err
		}
		nerr, err := getsockoptIntFunc(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_ERROR)
		if err != nil {
			return nil, os.NewSyscallError("getsockopt", err)
		}
		switch err := syscall.Errno(nerr); err {
		case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
		case syscall.EISCONN:
			return nil, nil
		case syscall.Errno(0):