gistfile1.txt

#include "stdafx.h"
#include "Discovery.h"

Discovery::Discovery(char* addr, int port, DiscoveryListener* l) {
	listener = l;
	int n;
	unsigned int length;
	struct sockaddr_in server, from;
	struct hostent *hp;
	char buffer[256];
   
	sock= socket(AF_INET, SOCK_DGRAM, 0);
	server.sin_family = AF_INET;
	hp = gethostbyname(addr);
	memcpy((char *)hp->h_addr, 
		(char *)&server.sin_addr,
		 hp->h_length);
	server.sin_port = htons(port+1);
	length=sizeof(struct sockaddr_in);
	memset(buffer, 0, 256);
	sendto(sock,"REQ",4,0,(const struct sockaddr *)&server,length);

	pthread_create(&thread, NULL, worker, this);
}

void* Discovery::worker(void* x) {
	Discovery* d = (Discovery*)x;

	char buf[1024];
	int fromlen = sizeof(struct sockaddr_in);

	struct sockaddr_in from;       
	while (1) {
		int n = recvfrom(d->sock, buf, 1024, 0, (struct sockaddr *)&from, &fromlen);
		char* s = new char[n+1];
		memcpy(s, buf, n+1);
		d->listener->OnNewServer(&from, s);
	}
}