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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include "clientserver.h"
void error(const char *msg)
{
perror(msg);
exit(EXIT_FAILURE);
}
int main(int argc, char **argv)
{
struct sockaddr_in si_local, si_remote;
int s;
int port;
int slen;
char buf[BUFLEN];
if (argc < 2) {
printf("Usage: %s port\n", argv[0]);
exit(1);
}
port = atoi(argv[1]);
slen = sizeof(si_remote);
if ((s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) {
error("socket");
}
memset((char *) &si_local, 0, sizeof(si_local));
si_local.sin_family = AF_INET;
si_local.sin_port = htons(port);
si_local.sin_addr.s_addr = INADDR_ANY;
if (bind(s, (const struct sockaddr *) &si_local, sizeof(si_local)) ==
-1) {
error("bind");
}
while (1) {
slen = sizeof(si_remote);
memset(buf, 0, sizeof(char) * BUFLEN);
memset(&si_remote, 0, sizeof(si_remote));
if (recvfrom
(s, buf, BUFLEN, 0, (struct sockaddr *) &si_remote,
&slen) == -1) {
error("recvfrom()");
} else {
printf("Received -- %s -- from %s:%d\n", buf,
inet_ntoa(si_remote.sin_addr),
ntohs(si_remote.sin_port));
printf("Sending -- %s -- to %s:%d\n", buf,
inet_ntoa(si_remote.sin_addr),
ntohs(si_remote.sin_port));
slen = sizeof(si_remote);
if (sendto
(s, buf, BUFLEN, 0, (struct sockaddr *) &si_remote,
slen) == -1) {
error("recvfrom()");
}
}
}
close(s);
exit(EXIT_SUCCESS);
}
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