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PublishedAPI for packages intended to be used by Plugin and Contrib authors, or 
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See also 
Developing plugins, 
Developer's Bible, 
Technical Overview
  internal package Foswiki::Engine::CLI  is a Foswiki::Engine 
Class that implements CGI scripts functionality when called from
command line or cron job
Refer to 
Foswiki::Engine documentation for explanation about methos below.