#!/bin/sh
#
#  Script to automatically add changebars to troff docs.
#
if [ $# -lt 1 ]; then
#
#  If user does not enter parameters, show usage info.
#
	echo
	echo "	changebar --> Usage:   changebar OLDFILE NEWFILE"
	echo
	echo "	Produces NEWFILE.chbar that is NEWFILE with changebars,"
	echo "	leaves original files intact."
	echo
else
#  Run a context diff on the two files
#
	diff -c $2 $1 > $1.diff
#
#  Install change bars in the context diff,
#  for ADDITIONS and MODIFICATIONS only.
#  DELETIONS not marked -- reverse the
#  sequence of the file names and run it
#  again to get an original file with
#  deletions and modifications marked.
#
	chbar < $1.diff > $1.patch
#
#  Run the patch program to install the
#  now-modified context diffs.
#
	patch -R < $1.patch
#
#  Remove the intermediate files;
#  assumes that all of the patches worked.
#
	rm $1.diff $1.patch
#
#  Translate ^G to \n, installed for
#  convenience to make patch work unmodified.
#  Name the filtered version as $2.chbar.
#
	tr '\007' '\012' < $1 > $2.chbar
#
#  Make the patched (intermediate) file removable
#
	chmod 666 $1
#
#  Patch renamed original file;
#  restore the original name
#
	mv $1.orig $1
#
#  Now tell the user what we did.
#
	echo 
	echo "All of the hunks should have succeeded"
	echo
	echo "There is now a new file named $2.chbar that is exactly"
	echo "like your file named $2, but it has changebars installed."
	echo
fi
