yesno

#!/bin/sh

# yesno
# https://www.github.com/kloverde/linux-utils
#
# Copyright (c) 2020, Kurtis LoVerde
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# This script exports a variable called YESNO which is
# guaranteed to have a value of Y or N (uppercase).

answer=""

while [ "${answer}" != "Y" -a "${answer}" != "N" ]
do
   read -p "${1} (Y/N) " answer
   answer=`echo "${answer}" | tr '[:lower:]' '[:upper:]'`
done

export YESNO=${answer}