gistfile1.txt

function check_space {
	if [[ $1 == *[bdks';''&'' ']* ]]
	then 	
    		return 0
	fi

	return 1
}

while :
do
	echo "Your input:"
	read input
	if check_space "$input" 
	then
		echo -e '\033[0;31mRestricted characters has been used\033[0m'
	else
		output="echo Your command is: $input"
		eval $output
	fi
done