#!/bin/rc
usage='usage: dup [-f] [-e ext] file ...'
fflag=0	# force dup
e=orig
while(~ $1 -*){
	switch($1){
	case -?*[e]*
		o=`{echo $1 | sed 's/(-[^e]+)([e])(.*)/\1 -\2 \3/'}
		shift
		*=($o(2) $o(3) $*)
	case -f
		fflag=1
		shift
	case -e
		shift
		e=$1
		shift
	case -*
		echo $usage
		exit usage
	}
}

if(~ $#* 0){
	echo $usage
	exit
}

# if $fflag != 0  we should check the validity of the operation
if(~ $fflag 0){
	for(f in $*){
		if(test -e $f.$e){
			echo $f.$e already exist!
			exit
		}
	}
}

for(f in $*){
	mv $f $f.$e		# keep original owner etc
	if(~ $status ?*)
		exit
	cp -x $f.$e $f
}