PRESENCE: fix log warning "use of uninitialized value ..." when using power set command without any argument. (Forum: #48499)

git-svn-id: https://svn.fhem.de/fhem/trunk@10686 2b470e98-0d58-463d-a4d8-8e2adae1ed80

fhem/CHANGED

@@ -1,5 +1,7 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+  - bugfix:  PRESENCE: fix log warning "use of uninitialized value ..." when 
+             using power set command without any argument.
   - added:   60_allergy: Allergy forecast data for Germany
   - feature: FB_CALLLIST: new attribute number-cmd to execute a FHEM command
              when clicking on a external number within the calllist. Can be any

fhem/FHEM/73_PRESENCE.pm

@@ -285,7 +285,7 @@ PRESENCE_Set($@)
         my %specials= (
         "%NAME" => $name,
         "%ADDRESS" => $hash->{ADDRESS},
-        "%ARGUMENT" => $a[2]
+        "%ARGUMENT" => (defined($a[2]) ? $a[2] : "")
         );
         
         $powerCmd= EvalSpecials($powerCmd, %specials);