How can I refuse a socket connection in C?

Question

If I want to accept a connection I call accept, but how can I refuse a connection?

In a working socket echo client I have this if statement. In the echo

Answer 1

A little late to the party, but you can use WSAAccept() instead of accept(). WSAAccept() has an optional callback function that allows you to take a peek at who's knocking at the door and decide if you want to answer. Your callback function can return the constants CF_ACCEPT, CF_REJECT and CF_DEFER. The first two are obvious. The 3rd one allows you to defer answering in case you need to decide later. Once you've decided for sure you call WSAAccept() again and either accept or reject.

Unfortunately, you have to either accept or reject in order to remove the entry from the front of the listen queue. The reason I say it's unfortunate is there is an obvious difference to the connecting machine between getting rejected and never getting a response (timeout).

If a hacker is using a port scanner they'll know you're listening on the port if you reject. At that point they can start hacking their way in. It would be nice to be able to remove the entry from the front of the queue without ever doing anything with it such that whoever's on the other end doesn't know you're listening on that port.