#!/bin/bash
#
# testextension - return true (zero) if one of the extensions matches,
# for example:
#
#       testextension foo.pdf pdf PDF ps PS     => returns 0
#       testextension foo.pdf gz Z              => returns 1

ext="${1##*.}"
while test -n "$2"; do
    test "$2" = "$ext" && exit 0
    shift
done

exit 1