c++ - 对 `__imp_WSACleanup' 的 undefined reference

Question

这是我使用 winsock 的第一个程序。如您所见，我有 #include <winsock2.h>并链接 ws2_32.dll ，但代码仍然无法编译:

#include<winsock2.h>
#pragma comment(lib, "ws2_32")
class CInitSock{
public:

    CInitSock(BYTE minorVer=2,BYTE majorVer=2){
        //initialize WS2_32.dll
        WSADATA wsaData;
        WORD sockVersion = MAKEWORD(minorVer,majorVer);
        if(::WSAStartup(sockVersion,&wsaData)!=0){
            exit(0);
        }
    }
    //release winSock libary
    ~CInitSock(){
        ::WSACleanup();
    } 
};

#include "CInitSock.h"
#include<stdio.h>
CInitSock initSock;
int main(void){
    char szHost[256];
    ::gethostname(szHost,256);
    hostent *phost = ::gethostbyname(szHost);
    in_addr addr;
    for(int i = 0;;i++){
        char *p = phost->h_addr_list[i];
        if(p==NULL){
            break;
        } 
        memcpy(&addr.S_un.S_addr,p,phost->h_length);
        char *szIp = ::inet_ntoa(addr);
        printf("%s \n",szIp);   
    }
}

这是错误:

mingw32-make.exe -f "D:\project\c_program\Makefile.win" all
g++.exe GetAllIPs.o -o win_socket.exe -L"D:/tools/develepment/Dev-Cpp/MinGW64/x86_64- w64-mingw32/lib" -L"D:/tools/develepment/Dev-Cpp/MinGW64/lib32" -static-libgcc -mwindows -g3


GetAllIPs.o: In function `main':
D:\project\c_program/GetAllIPs.cpp:6: undefined reference to `__imp_gethostname'
D:\project\c_program/GetAllIPs.cpp:7: undefined reference to `__imp_gethostbyname'
D:\project\c_program/GetAllIPs.cpp:15: undefined reference to `__imp_inet_ntoa'
GetAllIPs.o: In function `CInitSock::CInitSock(unsigned char, unsigned char)':
D:\project\c_program/CInitSock.h:10: undefined reference to `__imp_WSAStartup'
GetAllIPs.o: In function `CInitSock::~CInitSock()':
D:\project\c_program/CInitSock.h:16: undefined reference to `__imp_WSACleanup'
collect2.exe: error: ld returned 1 exit status

mingw32-make.exe: *** [win_socket.exe] Error 1

现在我完全糊涂了...

Answer 1

您使用的 pragma 仅适用于 Visual C++ 编译器，将被 gcc 忽略

#pragma comment(lib, "ws2_32")

您必须在 makefile 中手动添加 ws2_32.lib。喜欢:

-L"ws2_32"

(我猜它最后没有“.lib”)

在 g++ 行的末尾。您当然已经添加了我目前还没有的完整路径。