"Network Programming" uses Getnameinfo ()/getaddrinfo ()/inetpton ()

1. Brief

The previously used network programming function has now made a certain change, reported so 3 errors.

error C4996: ‘inet_ntoa‘: Use inet_ntop() or InetNtop() instead or define _WINSOCK_DEPRECATED_NO_WARNINGS to disable deprecated API warningserror C4996: ‘gethostbyaddr‘: Use getnameinfo() or GetNameInfoW() instead or define _WINSOCK_DEPRECATED_NO_WARNINGS to disable deprecated API warningserror C4996: ‘inet_ntoa‘: Use inet_ntop() or InetNtop() instead or define _WINSOCK_DEPRECATED_NO_WARNINGS to disable deprecated API warnings

2. Workaround 1

Right-click Properties-Property Page Select the SDL check box, general, C + +, select No.

3. Code resolution

Now that you have made it clear that you need to switch to a more secure function, just follow the requirements.

serverAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");//自己的IP或者127.0.0.1

Switch

//新改进代码InetPton(AF_INET, _T("127.0.0.1"), &serverAddr.sin_addr.s_addr);

GETHOSTBYADDR () switch to Getnameinfo ();

Inet_ntop () switch to getaddrinfo ();

The Modified code:

#include "stdafx.h" #include <WinSock2.h> #pragma comment (lib, "Ws2_32.lib") #include <ws2tcpip.h>/*1. Initializes the environment wsastartup2. Create socket Socket3. Binds socket Bind4. Listen for socket listen5. Handles socket connection ACCEPT6. Send receive Data send/recv7. Close socket closesocket8.    Clean up the Environment Wsacleanup*/int main () {//1. Initialize the environment WSAStartup wsadata WSD = {0};    int re = WSAStartup (Makeword (2, 2), &AMP;WSD);    if (Re! = 0) {return 0;}        if (Lobyte (wsd.wversion)! = 2 | |    Hibyte (wsd.wversion)! = 2) {return 0; }//2.    Create socket sockets Socket Listensock = socket (af_inet, sock_stream, ipproto_tcp);    if (Listensock = = invalid_socket) {return 0; }//3.    Bind socket bind sockaddr_in serveraddr;    serveraddr.sin_family = af_inet;        Serveraddr.sin_port = htons (0x5566); Old code//SERVERADDR.SIN_ADDR. S_un. S_ADDR = inet_addr ("127.0.0.1");//own IP or 127.0.0.1//New Improved Code Inetpton (Af_inet, _t ("127.0.0.1"), &serveraddr.sin_ad Dr.s_addr);    Re = Bind (Listensock, (SOCKADDR *) &serveraddr, sizeof (SERVERADDR)); 4.    Listener Socket Listen RE = Listen (Listensock, somaxconn); 5.    Handle socket connection Accept sockaddr_in clientaddr;    int size = sizeof (CLIENTADDR);    SOCKET Stoclientsock = Accept (Listensock, (SOCKADDR *) &clientaddr, &size);    Test get results//replace for new function view using result//old hostname hostent * phost = gethostbyaddr ((char *) &AMP;SERVERADDR.SIN_ADDR, 4, af_inet);        Old IP Address char * p = inet_ntoa (* (struct in_addr *) (*phost->h_addr_list));    New code Test///////////////////////////////////////////////////////////////////struct Addrinfo *ptr = NULL;    struct Addrinfo hints;    struct Addrinfo *result = NULL;    struct sockaddr_in *sockaddr_ipv4; Char Hostname[ni_maxhost]; Host name Char Servinfo[ni_maxserv]; Specific connection succeeded Port Getnameinfo (struct sockaddr *) &serveraddr, sizeof (struct sockaddr), hostname, NI    _maxhost, Servinfo, Ni_maxserv, Ni_numericserv); ZeromemorY (&hints, sizeof (hints));    hints.ai_family = Af_unspec;    Hints.ai_socktype = Sock_stream;    Hints.ai_protocol = ipproto_tcp;    GETADDRINFO (hostname, servinfo, &hints, &result);            for (ptr = result; ptr! = NULL; ptr = ptr->ai_next) {switch (ptr->ai_family) {case AF_UNSPEC:            printf ("unspecified\n");        Break            Case af_inet:printf ("af_inet (IPv4) \ n");            Sockaddr_ipv4 = (struct sockaddr_in *) ptr->ai_addr;            printf ("\tipv4 address%s\n", Inet_ntoa (SOCKADDR_IPV4-&GT;SIN_ADDR));        Break }}/////////////////////////////////////////////////////////////////////6.1 sends data send char buf[100] = "    Hello socket client,from server! ";    Re = Send (Stoclientsock, buf, strlen (BUF), 0);    if (re = = Socket_error) {goto over;    }//6.2 receive data recv re = recv (Stoclientsock, buf, sizeof (BUF), 0); if (re = = invalid_socket) {goto OVer }over://7.    Close socket closesocket closesocket (listensock);    Closesocket (Stoclientsock); 8.    Clean up the Environment WSACleanup WSACleanup (); return 0;}

Network programming uses Getnameinfo ()/getaddrinfo ()/inetpton ()