UDP封装

const int UDP_BUFFER_SIZE = 128;

class myudpsocket
{
public:
SOCKET MySockOpen(unsigned short portNum);

int MySockSend(const char *msg, int len, string ipAddr,unsigned short portNum);
int MySockRecv();
int MySockRecv(void *buf, int len);

int MySockClose(void);

void MyGetBuff(char **pBuffer);

private:
unsigned short port; //local bind port
SOCKET sockUdp; //local open socket

struct sockaddr_in localAddr;
struct sockaddr_in remoteAddr; // can be used to store the remote peer's address,but not always necesssary!

char pbuff[UDP_BUFFER_SIZE]; //default buffer for send or recv
};