implemented error message for nonexistent key

tomcat

@@ -2,6 +2,7 @@
 
 set -e
 
+argv0="$0"
 argv1="$1"
 argv2="$2"
 
@@ -59,6 +60,9 @@ if test -n "$ARR"; then
 	# change the line delineator to newlines for parsing and output the result
 	printf "%s\n" "$VAL" | sed 's/	/\n/g' | head -n "$ARR" |\
 		tail -n 1
+elif !  test -n "$VAL"; then
+	printf "%s: %s: no such key or table\n" "$argv0" "$argv1"
+	exit 65 # sysexits(3) EX_DATAERR
 else
 	printf "%s\n" "$VAL"
 fi