Detecting if a program is open

I'm trying to detect whether a specific program is open, and then keep track of how long it stays open. Any ideas?

I take it the program you want to track is not one you have written?!
what operating system? Cant think of any portable way of doing this without conditional compilation.

Unless you want to use a mutex, if you know the file name then peruse this: http://msdn.microsoft.com/msdnmag/is...A/default.aspx

No it's not a program I've written... it would be running under Windows XP. Thanks for your help. I haven't finished checking out that website, Ken, but it looks helpful. Thank you!