Thread: reading a file to send to an http client

Code:

SOCKET establish (unsigned short portnum)
{
 char computer_name[256];
 SOCKET new_sock;
 struct sockaddr_in sa;
 struct hostent     *hp;

 memset      (&sa, 0, sizeof (struct sockaddr_in));
 gethostname (computer_name, sizeof (computer_name));

 hp = gethostbyname (computer_name);
 if (hp == NULL)
  return INVALID_SOCKET;

 sa.sin_family = hp->h_addrtype;
 sa.sin_port   = htons (portnum);
 
 new_sock = socket (AF_INET, SOCK_STREAM, 0);
 
 if (new_sock == INVALID_SOCKET)
  return INVALID_SOCKET;
 
 if (bind (new_sock, (struct sockaddr *) &sa, sizeof (struct sockaddr_in)) == SOCKET_ERROR)
 {
  closesocket (new_sock);
  return INVALID_SOCKET;
 }

 if (listen (new_sock, 20) == SOCKET_ERROR)
 {
  closesocket (new_sock);
  return INVALID_SOCKET;
 }
 cout << "Still ok at return";
 return new_sock;
}

does creating the socket even work?

About the red-marked parts:
What's that? Are you trying to get the servers hostname and resolve it? If that even works, you are not passing the resolved address anywhere, so you can clear that.
But I doubt, this even works

About the blue-marked parts:
Look closer, its obvious why this can not work.
1. pass AF_INET to sin_family. If youre coding the server for the internet or other IP-networks, this is always right.

2. I can't see any assignment to sin_addr here ... despite the fact that you were trying to resolve the address above, I recommend you to use this:

Code:

sa.sin_addr.s_addr = INADDR_ANY;

This is needed to tell the machine, which interfaces to use. INADDR_ANY would be 0.0.0.0, but you could also assign the ip address of a NIC or even the loopback interface (127.0.0.1) to restrict the server to listen on that NICs (or the loopback adapter)

3. This is actually not a big deal, but socket() is supposed to get passed PF_INET, not AF_INET. This still works, because they are identical. Though they were both supposed to have different purposes. So I think it's more correct to use PF_INET, but that's your choice
(This doesn't apply to the struct sockaddr_in!)

I hope this helps solving