Why socket(PF_INET,SOCK_STREAM,0) returns -1?

I trying to create a socket application on visual studio c++, but I can't.

The problem is int listen_sock = socket(PF_INET,SOCK_STREAM,0) returns -1 and I don't know 开发者_运维问答why...

What am I doing wrong?

What does WSAGetLastError return? Did you call WSAStartup before doing this call?

You should print the error (using GetLastError). I suspect you are not initializing things:

WSADATA wsaData = {0};
WSAStartup(MAKEWORD(2, 2), &wsaData);