em - Empty a stack					Matthew Miller


EXAMPLES:
em			empty stack 2 (fill it with zeros)
em 7			empty stack 7 in the current foreground
			directory
em 13 dt:		empty stack 13 in the current background
			directory
em 11 rev:		recover stack 11 in the current foreground
			directory if possible
em 1_6			empty stacks 1 through 3 in core and 4
			through 6 in the current foreground
			directory

DESCRIPTION:
Em is used to empty a range of stacks which is either in core or on disk.
If 'sk' is below 4, then the stack in core will be emptied.  If it is
equal to or above 4, then the stack in the directory 'f' will be
emptied.

When a stack in core is emptied, it is filled with zeros and all the
data is lost.  When a stack on disk is emptied, a flag is set that
tells COMB it is emptied.  Stacks on disk may be recovered with the
reverse empty flag ('rev') if the space they occupy has not been
overwritten by a store.

The current foreground stacks directory is used unless the dt: flag is
given.

This document was last updated on Tue Oct 17 16:24:05 EDT 2000 by Marc W. Pound.