simple udp

/****************************************************************************
@File Name: server.cpp
@Author: wangzhicheng
@mail: 2363702560@qq.com
@Created Time: Sun 05 Mar 2017 03:47:08 PM CST
****************************************************************************/
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <iostream>
using namespace std;
static const int PORT_SERV = 8888;
int main(int argc, char*argv[])
{
	int sock;
	struct sockaddr_in from; 
	struct sockaddr_in local;
	socklen_t from_len = sizeof(from); 
	int n;  
	char buf[128];
	sock = socket(AF_INET, SOCK_DGRAM, 0);
	if(sock < 0)
	{
		cerr << "sock init failed...!" << endl;
		return -1;
	}
	local.sin_family = AF_INET;  
	local.sin_port = htons(PORT_SERV); 
	local.sin_addr.s_addr = htonl(INADDR_ANY);
	if(bind(sock, (struct sockaddr*)&local,sizeof(local)) < 0)
	{
		cerr << "bind failed...!" << endl;
		return -2;
	}
	n = recvfrom(sock, buf, 128, 0, (struct sockaddr*)&from, &from_len);
	if(n <= 0)
	{
		cerr << "recv failed...!" << endl;
		return -3;
	}
	cout << buf << endl;
	close(sock);

	return 0;
}

/****************************************************************************
@File Name: client.cpp
@Author: wangzhicheng
@mail: 2363702560@qq.com
@Created Time: Sun 05 Mar 2017 03:59:34 PM CST
****************************************************************************/
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <iostream>
using namespace std;
int main(int argc, char*argv[])
{
	int sock;
	struct sockaddr_in addr_serv;  
	struct sockaddr_in local;
//	struct sockaddr_in to;
	socklen_t len = sizeof(local);
	int n;
	char buf[128] = {0};
	sock = socket(AF_INET, SOCK_DGRAM, 0);
	if(sock < 0)
	{
		cerr << "sock init failed...!" << endl;
		return -1;
	}
	strcpy(buf, "hello world...!\n");
	addr_serv.sin_family = AF_INET; 
	addr_serv.sin_addr.s_addr = inet_addr("10.204.176.40");
	addr_serv.sin_port = htons(8888);
//	to.sin_family = AF_INET;
//	to.sin_port = htons(8888);
//	to.sin_addr.s_addr = inet_addr("127.0.0.1");
	if(connect(sock, (struct sockaddr*)&addr_serv, sizeof(addr_serv)) < 0)
	{
		cerr << "client connect server failed...!" << endl;
		return -2;
	}
	getsockname(sock, (struct sockaddr*)&local, &len);
	cout << "UDP local addr = " << inet_ntoa(local.sin_addr) << endl;
	n = sendto(sock, buf, sizeof buf, 0, (struct sockaddr*)&addr_serv, sizeof(addr_serv));
	if(n <= 0)
	{
		cerr << "client send failed...!" << endl;
		return -3;
	}
	close(sock);

	return 0;
}