UDP socket 的使用 (part 2)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <winsock.h>

const int SERVERPORT= 4950; // the port users will be connecting to
const int MYPORT=4900; // the local port
#define SERVER_IP "192.168.136.93"

void init_win_socket();
void clean_win_socket();
void close_win_socket(SOCKET &soc_handle);

//this socket is intend to use as a simple client
int  main()
{
puts("start main client...");
int numBytes=0;
int ret=0;
char sendBuf[]="Hello, this is used to test UDP socket!/0";

//init windows socket
init_win_socket();

SOCKET local_sock_fd;
struct sockaddr_in main_soc_addr;
struct sockaddr_in client_soc_addr;

//create the client socket
local_sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
if(local_sock_fd ==-1)
{
puts("CREATE SOCK ERROR:");
}
//configure the client's local socket addr
client_soc_addr.sin_family = AF_INET;
client_soc_addr.sin_port = htons(MYPORT);
client_soc_addr.sin_addr.s_addr = htonl(INADDR_ANY);
memset(client_soc_addr.sin_zero, '/0', sizeof(client_soc_addr.sin_zero));

//bind the socket
ret = bind(local_sock_fd, (struct sockaddr *)&client_soc_addr, sizeof(client_soc_addr));
if(ret==-1)
{
puts("BIND SOCK ERROR:");
}

//configure the client's server socket addr
main_soc_addr.sin_family = AF_INET;
main_soc_addr.sin_port = htons(SERVERPORT);
main_soc_addr.sin_addr.s_addr = inet_addr(SERVER_IP);
memset(main_soc_addr.sin_zero, '/0', sizeof(main_soc_addr.sin_zero));

//now,we can send data to the server
numBytes =sendto(local_sock_fd, sendBuf, strlen(sendBuf),
0, (struct sockaddr*)&main_soc_addr, sizeof(sockaddr));
if(numBytes ==-1)
{
puts("SEND DATA ERROR:");
}

//close and clean the windows sockets
close_win_socket(local_sock_fd);
clean_win_socket();

puts("any key to continue...");
getchar();
return 0;
}

//init windows socket
void init_win_socket()
{
WSADATA wdata;
if(WSAStartup(MAKEWORD(2,2), &wdata)!=0)
{
puts("WAS ERROR:");
}
}

//close windows socket
void close_win_socket(SOCKET &soc_handle)
{
if(soc_handle>0)
{
closesocket(soc_handle);
}
}

//clean windows socket
void clean_win_socket()
{
WSACleanup();
}