check_systemdunit add -r REGEX

docs/20_Checks/check_systemdunit.md

@@ -16,7 +16,7 @@ A unit is everything listed by systemctl command - services, timers, targets, ..
 ______________________________________________________________________
 
 CHECK_SYSTEMDUNIT
-v1.1
+v1.2
 
 (c) Institute for Medical Education - University of Bern
 Licence: GNU GPL 3
@@ -30,13 +30,18 @@ The status is unknown if the command systemctl is not found.
 The status is critical if the service does not exist or is not running.
 
 SYNTAX:
-  check_systemdunit [-h|-l|-s] UNIT
+  check_systemdunit [-h|-l|-s|-r] UNIT
 
 OPTIONS:
 
   -h     this help
   -l     list all units
   -s     list service units
+  -r     handle UNIT as a regex and search for a single unit. A uniq regex
+         is needed to match a single unit. The initial idea was to match a
+         servie that has different service names on differen os eg.
+         - apache2 vs httpd
+         - mysld vs mariadb
 
   UNIT   Name of a unit - see output of 'systemctl' 
 
@@ -49,6 +54,10 @@ EXAMPLES:
   check_systemdunit nginx.service
          show status of nginx webservice
 
+  check_systemdunit -r "(apache2|httpd)\.service"
+         Detect name of Apache httpd service by given regex and show status
+         of the found service name
+
 ```
 
 ## Examples