>How do I capture the parts of a filename? For example, if the name of a file is image0001.jpg, I want to define lcprefix as "image0001" and lcSuffix as "jpg". I can't find this anywhere in the VFP6 online documentation, which is frustratingly difficult to use.

look for JUSTSTEM() and JUSTEXT() commands in the help
You can also get this functionality using the regular VFP character handling commands (AT,LEFT,RIGHT etc.)

Arnon