I have a client with numerous Foxpro 2.6 DOS applications. They want to limit the users to only running one instance of the programs. These engineers will have the same program open 8 or 9 times and wonder why their computer is running slow. I know how to do it in windows and the method I use for DOS won't work.

Unfortunately, CLOSE ALL is spread throughout the code of all the programs so using a low level file open/create to make a file that only exists during execution of the program won't work. This is the method I've used in the past.

Help!