socket总是connect失败

两段程序，客户端client和服务端server。如果都在同一个电脑运行并把ip地址设为127.xx.xx.xx
是可以连接成功的。
但是，如果分开到两台电脑(当然ip地址也设为服务端的ip),就不行。

服务端server代码：

#include "stdafx.h"
#include
#include
#include
using namespace std ;
#pragma comment(lib, "ws2_32.lib")

#define LISTEN_MAX_COUNT 5
//服务器
DWORD WINAPI AnswerThread(LPVOID lparam)
{
printf("Thread ID:%4d create!\n", GetCurrentThreadId());
int ret;
char buf[50] = { 0 };
char sendBuf[80] = { 0 };
SOCKET clientSocket = (SOCKET)(LPVOID)lparam;
while (true)
{
memset(buf, 0, sizeof(buf));
ret = recv(clientSocket, buf, sizeof(buf), 0);
if (ret<=0)
{
break;
}
printf("revc: %s\n", buf);
sprintf_s(sendBuf, "Thread ID:%4d revced", GetCurrentThreadId());
ret = send(clientSocket, sendBuf, strlen(sendBuf) + sizeof(char), 0);
if (ret <= 0)
{
break;
}
}
printf("Thread ID:%4d stop!\n", GetCurrentThreadId());
closesocket(clientSocket);
return 1;
}

int _tmain(int argc, _TCHAR* argv[])
{

WORD wVersionRequested;
WSADATA wsaData;
wVersionRequested = MAKEWORD(1, 1);
if (WSAStartup(wVersionRequested, &wsaData) == INVALID_SOCKET)
{
    return 0;
}

if (LOBYTE(wsaData.wVersion) != 1 ||
    HIBYTE(wsaData.wVersion) != 1) {
    WSACleanup();
    return 0;
}
SOCKET sockSrv = socket(AF_INET, SOCK_STREAM, 0);
int len = sizeof(SOCKADDR);
SOCKADDR_IN clientAddr;
SOCKADDR_IN serviceAddr;
serviceAddr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
serviceAddr.sin_family = AF_INET;
serviceAddr.sin_port = htons(8000);

if (bind(sockSrv, (SOCKADDR*)&serviceAddr, len) == INVALID_SOCKET)
{
    printf("failed bind!\n");
    closesocket(sockSrv);
    WSACleanup();
    return 0;
}
if (listen(sockSrv, LISTEN_MAX_COUNT) == SOCKET_ERROR) {
    printf("Listen failed with error: %ld\n", WSAGetLastError());
    closesocket(sockSrv);
    WSACleanup();
    return 0;
}


SOCKET  sockClient;
HANDLE  hThread = NULL;
DWORD    dwThreadId;
while (1)
{
    sockClient = accept(sockSrv, (SOCKADDR*)&clientAddr, &len);

    Sleep(1000);
    hThread = CreateThread(NULL, NULL, AnswerThread, (LPVOID)sockClient, 0, &dwThreadId);

    if (hThread == NULL)
    {
        printf("CreatThread AnswerThread() failed.\n");
    }
}

closesocket(sockSrv);
WSACleanup();
return 0;

}

客户端 client 代码：

#include "stdafx.h"
#include
#include

#pragma comment( lib, "ws2_32.lib" )
//客户端
int _tmain(int argc, _TCHAR* argv[])
{

WORD wVersionRequested;
WSADATA wsaData;
int err;

wVersionRequested = MAKEWORD(1, 1);
if (WSAStartup(wVersionRequested, &wsaData) == INVALID_SOCKET)
{
    return -1;
}

if (LOBYTE(wsaData.wVersion) != 1 ||
    HIBYTE(wsaData.wVersion) != 1) {
    WSACleanup();
    return -1;
}


SOCKET sockClient = socket(AF_INET, SOCK_STREAM, 0);
int len = sizeof(SOCKADDR);

SOCKADDR_IN local;
local.sin_addr.S_un.S_addr = inet_addr("222.66.117.26");
local.sin_family = AF_INET;
local.sin_port = htons(8000);

if (connect(sockClient, (SOCKADDR*)&local, len) == INVALID_SOCKET)
{
    printf("connect error/n"); 
    return 0;
}

char inputBuf[30];
char recvBuf[50];
int ret;

// while (scanf_s("%s", inputBuf, sizeof(inputBuf)) != EOF)
while (gets_s(inputBuf))
{
if (strcmp(inputBuf, "stop") ==0)
{
break;
}
ret = send(sockClient, inputBuf, strlen(inputBuf) + sizeof(char), 0);
if (ret<=0)
{
printf("send failed!\n");
break;
}
ret = recv(sockClient, recvBuf, sizeof(recvBuf), 0);
if (ret <= 0)
{
printf("recv failed!\n");
break;
}
printf("my reply is : %s\n", recvBuf);
//printf("%s\n", inet_ntoa(local.sin_addr));
}

closesocket(sockClient);
WSACleanup();
return 0;

}

客户端报错“connect error”，大家看看问题在哪里？

两台机器的ip可以ping通吗

SOCKADDR_IN local;
local.sin_addr.S_un.S_addr = inet_addr("222.66.117.26");
local.sin_family = AF_INET;
local.sin_port = htons(8000);

上頭的寫法已經被正式停用了, 改寫成下面這樣 就會工作 !!

struct addrinfo *result = NULL, *ptr = NULL, local;
int iResult;

ZeroMemory( &hints, sizeof(hints) );
local.ai_family = AF_UNSPEC;
local.ai_socktype = SOCK_STREAM;
local.ai_protocol = IPPROTO_TCP;

// Resolve the server address and port
iResult = getaddrinfo("222.66.117.26", "8000", &local, &result);

sorry 忘記修改 hint ==> local

ZeroMemory( &hints, sizeof(hints) ); ==>
ZeroMemory( &local, sizeof(local) );

先用另一台機子 Dos command, 下達這個口令

C:\> telnet 222.66.117.26 8000

如果 server 通了, 會看到 server 吐出來的資料, 或是不通, 則會有如下的畫面

C:\>telnet 222.66.117.26 8000
正連線到 222.66.117.26...無法開啟到主機的連線， 在連接埠 8000: 連線失敗

這樣便可知道你的server 是否有再 listen.

確認 server 通了. 再運行你的 client.

查看一下权限是否开启