Fis systemd support on debian system version 13 (trixie) or newer.

install_vacation.sh

@@ -95,6 +95,16 @@ echo_skipped() {
    echo -e "\033[75G[ \033[30m\033[1mskipped\033[m ]"
 }
 
+# -Is systemd supported on this system?
+# -
+systemd_supported=false
+systemd=$(which systemd)
+systemctl=$(which systemctl)
+
+if [[ -n "$systemd" ]] || [[ -n "$systemctl" ]] ; then
+   systemd_supported=true
+fi
+
 
 if [ "$POSTFIX_DB_TYPE" = "postgres" -o  "$POSTFIX_DB_TYPE" = "postgresql" -o "$POSTFIX_DB_TYPE" = "pgsql" -o "$POSTFIX_DB_TYPE" = "psql" ];then
    POSTFIX_DB_TYPE=pgsql