>This process may run as a batch process. Right now I'm testing it from GUI, but we may want to try it to run in batch mode. However, I don't want to make this program slower than it has to be. Can you find out from prg the name of exe that called it? If it's batch, let it fail, otherwise we may use your suggestion and ask user for file location.

One of following should provide you with an answer: PROGRAM(), SYS(16), _VFP.ServerName, ASTACK().

Another solution would be to store the location of the program in question in the registry or INI file at the time of installation.