socket编程之inet_addr和inet_ntoa

inet_addr 将字符串形式的IP地址 -> 网络字节顺序  的整型值

inet_ntoa 网络字节顺序的整型值 ->字符串形式的IP地址

#define _WINSOCK_DEPRECATED_NO_WARNINGS
#include<WinSock2.h>
#include<iostream>
using namespace std;

#pragma comment(lib, "ws2_32.lib")

int main()
{
    WORD wVersionRequested;
    WSADATA wsaData;
    int err;

    wVersionRequested = MAKEWORD(1, 1);

    err = WSAStartup(wVersionRequested, &wsaData);
    if (err != 0) {
        return 0;
    }


    char ip1[] = "192.168.0.74";
    char ip2[] = "211.100.21.179";
    struct in_addr addr1, addr2;
    long l1, l2;
    l1 = inet_addr(ip1);   //将字符串形式的IP地址 -> 网络字节顺序  的整型值
    l2 = inet_addr(ip2);
    printf("IP1: %s
 IP2: %s
", ip1, ip2);
    printf("Addr1: %ld
 Addr2: %ld
", l1, l2);

    memcpy(&addr1, &l1, 4); //复制4个字节大小  
    memcpy(&addr2, &l2, 4);
    printf("%s <--> %s
", inet_ntoa(addr1), inet_ntoa(addr2)); //注意：printf函数自右向左求值、覆盖  
    printf("%s
", inet_ntoa(addr1)); //网络字节顺序的整型值 ->字符串形式的IP地址  
    printf("%s
", inet_ntoa(addr2));

    getchar();
    return 0;
｝