#! /bin/sh

# apply-sed -- apply sed to each input line, replacing it per result
# $Id: apply-sed,v 1.1 1998/09/06 23:18:35 cdua Exp cdua $
# Carlos Duarte, 980802

#trap -- 'rm -f /tmp/xpto' EXIT SIGINT

USAGE="\
usage: $0 [-hn] [-i[xxx]] { -e line -f file ... | 'script' } input

  -h         this help
  -e line    line is added to the script
  -f file    file contents are added to script
  -i[xxx]    keep backup of original file into file.xxx (xxx defaults to bak)
  'script'   specify the whole script, do not coexist with -e or -f

aplly sed to each input file, replacing it by the resulting output
of _each_ one
"

while : ; do
	case x"$1" in 
	x-h)	echo "$USAGE"; exit 1 ;;
	x-n)	N=-n ;;
	x-e)	S="$S -e '$2'"; shift ;;
	x-f) 	S="$S -f '$2'"; shift ;;
	x-i)	BAK=`echo $1|cut -c2-` 
		test x"$BAK" = x && BAK=bak
		;; 
	x--)	shift; break ;;
	x-?)	echo "invalid option -- `echo $1|cut -c2-`"
		echo "$USAGE"; exit 1 ;;
	*)	break ;;
	esac
	shift
done

if test "$S"x = x ; then
	if test $# -eq 0; then echo "$USAGE"; exit 1; fi
	S="'$1'"
	shift
fi

temp=/tmp/apsd.$$.
v=1
while test -f $temp$v || test -f $temp$v; do
	v=`expr $v + 1`
done
temp=$temp$v

if test $# -eq 0; then echo "$USAGE"; exit 1; fi
for file
do
	if eval sed $N "$S" < $file > $temp; then 
		test x"$BAK" != x && mv $file $file$BAK
		mv -f $temp $file
	else
		rm -f $temp
	fi
done