#! /bin/sh 

# dupfiles -- print duplicated files on supplied dirs 
# Carlos Duarte, 970425/980724

USAGE="\
usage: $0 [-h] dirs...

  -h      this help

print duplicated file names found at dirs. 
xx.gz, xx.Z and xx, are seen with same filenames.
"

while : ; do
	case x"$1" in 
	x-h)	echo "$USAGE"; exit 1 ;;
	x--)	shift; break ;;
	x-?)	echo "invalid option -- `echo $1|cut -c2-`"
		echo "$USAGE"; exit 1 ;;
	*)	break ;;
	esac
	shift
done

# if _must_ accept one extra argument after options
if test $# -eq 0; then echo "$USAGE"; exit 1; fi

# add a slash in front of each dir-- some finds will read dir contents, 
# if name is a symlink pointing to a dir
for i 
do
	test -d $i || continue
	d="$d $i/"
done
find $d ! -type d -print | awk '
{
	n = split($0, a, "/")
	sub("\.gz$", "", a[n])
	sub("\.Z$", "", a[n])
	dups[a[n]] = dups[a[n]] $0 "\n" 
}

END {
	for (d in dups) {
		x = dups[d]
		if (match(x, "\n") != length(x)) 
			print x
	}
}'