Cygwin GCC編譯錯誤

Question

我試圖在CYGWIN gcc中編譯C套接字程序，但是當我編譯客戶端程序時，出現以下錯誤

client.h: In function ‘error’:
client.h:11:5: warning: incompatible implicit declaration of built-in function ‘exit’ [enabled by default]
     exit(1);
     ^
client.h: In function ‘main’:
client.h:30:9: warning: incompatible implicit declaration of built-in function ‘exit’ [enabled by default]
         exit(0);
         ^
client.h:36:5: warning: passing argument 2 of ‘connect’ from incompatible pointer type [enabled by default]
     if(connect(sockfd,&serv_addr,sizeof(serv_addr)) < 0)
     ^
In file included from client.h:3:0:
/usr/include/sys/socket.h:28:7: note: expected ‘const struct sockaddr *’ but argument is of type ‘struct sockaddr_in *’
   int connect (int, const struct sockaddr *, socklen_t);
       ^

當我嘗試編譯服務器程序時，出現以下錯誤

server.h: In function ‘error’:
server.h:8:5: warning: incompatible implicit declaration of built-in function ‘exit’ [enabled by default]
     exit(1);
     ^
server.h: In function ‘main’:
server.h:18:9: warning: incompatible implicit declaration of built-in function ‘exit’ [enabled by default]
         exit(1);
         ^
server.h:23:5: warning: incompatible implicit declaration of built-in function ‘bzero’ [enabled by default]
     bzero((char *) &serv_addr, sizeof(serv_addr));
     ^
server.h:32:64: error: ‘client’ undeclared (first use in this function)
     newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &client);
                                                                ^
server.h:32:64: note: each undeclared identifier is reported only once for each function it appears in

那么解決方案是什么

Answer 1

客戶端代碼中的錯誤是因為您將指向struct sockaddr_in的指針傳遞給了一個參數，該參數期望它是指向struct sockaddr的指針。 錯誤消息基本上說明了一切。 服務器代碼中的錯誤是因為未在任何地方聲明變量client 。

這些警告是由於不包含包含exit聲明（include stdlib.h ）和bzero （include strings.h ）的適當包含文件引起的。 因此，您將獲得一個隱式聲明，並且由於編譯器將這些函數視為標准的內置函數，因此它在警告中也提到了這一點。

Answer 2

好了，問題是我試圖在Windows中編譯Linux程序。