宠物包装设计:winsocket编程中condef.h打不开，为什么？如何解决？

#include<winsock.h>
#include<stdio.h>
#pragma hdrstop
#include<condefs.h>
//---------------------------------------------------------------------------

#pragma argsused
int main(int argc,char *argv[])
{WORD wVersionRequested;
WSADATA wsaData;
wVersionRequested=MAKEWORD(2,0);
int err=WSAStartup(wVersionRequested,&wsaData);
if(err=-1)
{perror("WSAStartup");
exit(1);
}
int sock,length,msgsock;
struct sockaddr_in server;
char buf[]="this a test";
sock=socket(AF_INET,SOCK_STREAM,0);
if(sock<0)
{perror("opening steam socket");
exit(1);
}
server.sin_family=PF_INET;
server.sin_port=htons(7803);
server.sin_addr.s_addr=inet_addr("210.43.7.23");
msgsock=connect(sock,(struct sockaddr*)&server,sizeof(server));
Sleep(1000);
length=sizeof(buf);
int rval=send(sock,buf,length,MSG_OOB);
if(rval!=length)
{perror("sending stream error");
getchar();
exit(1);
}
closesocket(sock);
WSACleanup();
return 0;
}