GetGroupMatchCount( ) Counts the number of members in all groups matching the specified pattern
GetGroupMatchCount(groupmatch[@category])
Counts the number of members in all groups matching the regular expression specified by groupmatch. The result is stored in the ${GROUPCOUNT} variable.
Note that standard regular expressions are used in the groupmatch argument.
Always returns 0.
; get the count of members in any group that starts with tech
exten => 123,1,GetGroupMatchCount(tech.*)
exten => 123,2,SayNumber($GROUPMATCH)