The shell script 'changebar' uses Larry Wall's 'patch' program
to automatically install "change-bars" into an nroff/troff document.
The output of a context diff is modified by a lex-generated c program
to incorporate the changebars as though they are part of the differences
between the two files in the first place.  Then when patch runs, it
adds the change bars to the text.  After the patch processing, one more
post-processing operation is performed to add line feeds to the final
text, replacing ^G characters that were installed so that patch would
be able to run entirely unmodified.

My thanks to Larry Wall for creating 'patch' in the first place.
This program was prompted by a request by some of my engineers who
wanted to be able to "use SCCS to edit to my heart's content, then
when finally ready to reissue the document, have the change bars
installed automatically."  It seems to work, so here it is.  If
anyone makes any changes, I would like to hear about them; hope it
helps a few folks.

Released to the public domain, unsupported, do with it as you wish.

The files contained here are:
	changebar - a shell script
	chbar.lex - the lex script that compiles into a
		    context-diff examiner/modifier as a
		    preprocessing step before patch is used.
	chbar.1   - the man page that explains chbar.lex
	changebar.1 - the man page for the changebar script.
		      The FILES item will have to be modified
		      depending on where on your own system
		      you install things.

Rob Peck	Ardent Computer, 880 W. Maude Ave, Sunnyvale, Ca. 94086

