Exit if required binaries are not found

lib/dns.sh

@@ -9,12 +9,13 @@ if [ -z "${!DNS_KEYS[*]}" ]; then
 fi
 
 DNS_IP=${DNS_IP:-127.0.0.1}
-DIG=${DIG:-/usr/bin/dig}
+DIG=${DIG:-$(which dig)} || exit 1
-IDN2=${IDN2:-/usr/bin/idn2}
+IDN2=${IDN2:-$(which idn2)} || exit 1
-JQ=${JQ:-/usr/bin/jq}
+JQ=${JQ:-$(which jq)} || exit 1
-NAMED_CHECKCONF=${NAMED_CHECKCONF:-/usr/bin/named-checkconf}
+NAMED_CHECKCONF=${NAMED_CHECKCONF:-$(which named-checkconf)} || exit 1
-NSUPDATE=${NSUPDATE:-/usr/bin/nsupdate}
+NSUPDATE=${NSUPDATE:-$(which nsupdate)} || exit 1
-TERMINAL_WITH=${MAX_TERMINAL_WITH:-$(/usr/bin/tput cols)}
+TERMINAL_WITH=${MAX_TERMINAL_WITH:-$($(which stty) size | cut -d " " -f 2)} || exit 1
+
 
 ####################
 # global variables #