zdiff.in

采用 LZ77 运算规则 压缩及解压工具

:
#!/bin/sh

OPTIONS=
FILES=
for ARG
do
	case "$ARG" in
	-*)	OPTIONS="$OPTIONS $ARG";;
	*)	FILES="$FILES $ARG";;
	esac
done
if test -z "$FILES"; then
	echo "Usage: zdiff [diff_options] file [file]"
	exit 1
fi
set $FILES
if test $# -eq 1; then
	FILE=`expr $1 : '\(.*\)\.z' '|' $1`
	gzip -cd $FILE | ${DIFF-diff} $OPTIONS - $FILE
	STAT="$?"
elif test $# -eq 2; then
	case "$1" in
	*.z | *.Z)	case "$2" in
		*.z | *.Z)	F=`basename $2 .z`
			gzip -cd $2 > /tmp/$F.$$
			gzip -cd $1 | ${DIFF-diff} $OPTIONS - /tmp/$F.$$
			STAT="$?";;
		*)	gzip -cd $1 | ${DIFF-diff} $OPTIONS - $2
			STAT="$?";;
		esac;;
	*)	case "$2" in
		*.z | *.Z) gzip -cd $2 | ${DIFF-diff} $OPTIONS $1 -
			STAT="$?";;
		*)	${DIFF-diff} $OPTIONS $1 $2
			STAT="$?";;
		esac;;
	esac
	exit "$STAT"
else
	echo "Usage: zdiff [diff_options] file [file]"
	exit 1
fi