The pages on this site contain documentation for very old MS-DOS software,
purely for historical purposes.
If you're looking for up-to-date documentation, particularly for programming,
you should not rely on the information found here, as it will be woefully
out of date.
Undo (Alt+Bksp)
■ Reverses the most recent edit operation. Undo reverses
up to 20 previous edits.
■ Note: This command is not available if there are no
previous edit operations.