limiting number of clients that can connect to server

am writing a program on visual studio c. i am tryin to limit the number of clients that cud connect to my server lets say 3 for example.iv tried lots of things bt they arent working.Sum1 mentioned lukin at d Listen function to me but it still isnt workin.i attached d code of my server

i know how to do this in vb6 but i dont know this in c++

Wrong forum - this is for Vb.NET questions not C++