This article is from the Apple II Csa2 FAQ, by Jeff Hurlburt with numerous contributions by others.
You can discover the name of a ProDOS volume in a drive by doing a CAT. The volume name will be shown at the top of the screen listing (e.g. "/NARF/"). Another way-- one which works in programs as well as from the keyboard- - is to use the PREFIX command: PREFIX This command will normally return one of two results: o- If there is an established default prefix, then, the result will be the current default prefix. o- If there is no established default prefix, then, ProDOS will read the volume name of the volume in the default Slot and Drive. Note: PREFIX used in this way does not establish or change a pathname prefix. Booting clears any default prefix and sets default Slot/Drive to the boot drive. For your STARTUP program to discover the name of the volume on which it resides, it could execute the following: 100 PRINT CHR$(4)"PREFIX": INPUT"";P$ The volume name of the just booted disk (e.g. "/NARF/") will be saved in P$. ______________________ By: David Wilson