Due to operator precedence
Code:
if( testSocket = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP ) == INVALID_SOCKET)
is equivalent to(note brackets):
Code:
if( testSocket = (socket( AF_INET, SOCK_STREAM, IPPROTO_TCP ) == INVALID_SOCKET))
You want:
Code:
if((testSocket = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP )) == INVALID_SOCKET)
Also check the rest of your code for this common mistake.
P.S Please consider posting some code inline if possible. In this case the call to socket() and surrounding lines would have been sufficient.