Title:		tac

Author: 	Unknown off the net long ago, and
		Jay Lepreau
		Computer Science Dept.
		Univ. of Utah
		Salt Lake City, UT 84112
		801-581-4285
	
Net:		lepreau@utah-cs.arpa, {ihnp4,decvax}!utah-cs!lepreau
		Sometime lepreau@cs.utah.edu

tac ("cat" backwards) is a small program which prints file segments
in reverse order; by default it reverses by lines (like tail -r).
Besides being able to reverse a file by segments delimited by an
arbitrary string, its wins are that it is very fast, handles any
size segments and any size files.  These make it an excellent
filter, e.g. "tac <logfile> | egrep foo".

tmail is a trivial shell script which uses tac to display one's
mailbox, message by message, most recent first.

Potential improvements to tac which I would appreciate having fed back to me:
--segment by arbitrary regular expressions, but only if it's done
	w/o sacrificing the current speed for the default case.
--fix up handling of multiple files.
--nicely integrate with tail somehow.

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