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#include <stdlib.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
int main (int argc, char *argv[])
{
int s, len, o, port = 6666;
char buf[512];
struct sockaddr_in addr;
socklen_t addr_len = sizeof addr;
if (argc > 1)
port = atoi (argv[1]);
s = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
o = 1;
len = 4;
setsockopt (3, SOL_SOCKET, SO_REUSEADDR, &o, len);
addr.sin_family = AF_INET;
addr.sin_port = htons (port);
addr.sin_addr.s_addr = INADDR_ANY; /* receive broadcasts */
bind (s, (struct sockaddr *) &addr, sizeof addr);
for (;;) {
len = recvfrom (s, buf, sizeof buf, 0, (struct sockaddr *) &addr, &addr_len);
if (len < 0)
break;
write (1, buf, len);
}
return 0;
}
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