Initiating a file transfer with a CGI script in C++

I would like to write a CGI script that logs the IP address of the person that runs it and then initiates a file transfer. I know how to handle the logging of the client's IP address, but I have no idea where to begin with starting the file transfer. Can anyone point me in the right direction?

Do you mean initiating a file download by a user? Simply redirect them to the URL containing the file you wish them to download...

OK, how dod I dod that? :-)