timer/time_display.c
2024-06-22 17:51:55 -05:00

62 lines
1.3 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#define BUFLEN 512
#define PORT 1234
int main(void)
{
int ret;
int sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (sock == -1) {
perror("socket");
return -1;
}
struct sockaddr_in sockaddr = {0};
sockaddr.sin_family = AF_INET;
sockaddr.sin_port = htons(PORT);
sockaddr.sin_addr.s_addr = htonl(INADDR_ANY);
ret = bind(sock, (struct sockaddr *)&sockaddr, (sizeof (struct sockaddr_in)));
if (ret == -1) {
perror("bind");
return -1;
}
char buf[BUFLEN];
while (1) {
printf("Wait for datagram\n");
struct sockaddr_in src_addr = {0};
socklen_t addrlen = (sizeof (struct sockaddr_in));
ssize_t recv_len = recvfrom(sock, buf, BUFLEN, 0, (struct sockaddr *)&src_addr, &addrlen);
if (recv_len == -1) {
perror("recvfrom");
return -1;
}
buf[recv_len] = 0;
printf("Received packet from %s:%d\n", inet_ntoa(src_addr.sin_addr), ntohs(src_addr.sin_port));
printf("Data: %s\n", buf);
/*
//now reply the client with the same data
if (sendto(s, buf, recv_len, 0, (struct sockaddr*) &si_other, slen) == -1) {
die("sendto()");
}
*/
}
close(sock);
return 0;
}