#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define PORT 12342

int main(void)
{
	int s, cc;
	struct sockaddr_in addr;

	if ((s = socket(PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP)) < 0) {
		perror("socket");
		exit(1);
	}

	memset(&addr, '\0', sizeof(addr));
	addr.sin_family = AF_INET;
	addr.sin_addr.s_addr = INADDR_ANY;
	addr.sin_port = htons(PORT);

	if (bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
		perror("bind");
		exit(1);
	}
	if (listen(s, 5) < 0) {
		perror("listen");
		exit(1);
	}

	for (;;) {
		char buf[128];
		struct iovec iov[1] = {{.iov_base = buf, .iov_len = sizeof(buf)}};
		struct msghdr msg = {
			.msg_name = &addr,
			.msg_namelen = sizeof(addr),
			.msg_iov = iov,
			.msg_iovlen = sizeof(iov)/sizeof(iov[0]),
			.msg_control = NULL,
			.msg_controllen = 0,
			.msg_flags = 0
		};

		printf("Waiting for message\n");

		cc = recvmsg(s, &msg, 0);

		printf("Got msg, len = %d\n", cc);

		sendmsg(s, &msg, 0);
	}
}