static int set_send_buffer_size(int sk, int size)
{
	socklen_t optlen = sizeof(size);

	if (setsockopt(sk, SOL_SOCKET, SO_SNDBUF, &size, optlen) < 0) {
		int err = -errno;
		error("setsockopt(SO_SNDBUF) failed: %s (%d)", strerror(-err),
									-err);
		return err;
	}

	return 0;
}
static int set_send_buffer_size(int sk, int size)
{
	socklen_t optlen = sizeof(size);

	if (setsockopt(sk, SOL_SOCKET, SO_SNDBUF, &size, optlen) < 0) {
		int err = -errno;
		error("setsockopt(SO_SNDBUF) failed: %s (%d)", strerror(-err),
									-err);
		return err;
	}

	return 0;
}