How to end SQL Prompt programatically?

I only wanted to have SQL Prompt running when I was using Query Analyzer, so I wrote a little C++ program to start QA and then start SQL Prompt and wait until all QA instances are closed before ending SQL Prompt.

However, I can't seem to close SQL Prompt programatically.

Anyone have any idea how to do this (besides using the TerminateProcess API which is quite brutal...)?

Thanks.