3.  Control Messages

     Like C News, INN implements all control messages other than  cancel
as  shell  scripts.  The number and type of parameters is different from
that of C News.  All  control  messages  consult  the  file  control.ctl
before  acting on the message.  If the sender's address matches with the
list of authorized addresses (e.g., "tale@uunet.uu.net", "*", etc.),
the   control   message  is  either  acted  upon,  mailed  to  the  news
administrator,    or    logged.     For    example,    messages     from
"tale@uunet.uu.net" (the current moderator of news.announce.newgroups)
are honored.

     The "control", "junk", and "to" newsgroups can be  explicitly
sent or not sent.  See doc/newsfeeds.5 and doc/innd.8.

     The ctlinnd program is what really directs the server to create  or
remove  newsgroups.   This  results  in  a  semi-recursive process:  the
control message arrives, and a script is invoked to process the message.
If  approved,  the  script invokes ctlinnd to send a message back to the
server telling it to create or remove the group.