LIST(ADM)                            UNIX System V



     Name
          list - list processor channel for MMDF


     Syntax
          list


     Description
          List is an MMDF channel program for handling mailing  lists.
          The  channel functions as a feed-through between deliver and
          submit. The list channel has its own host table  and  domain
          table  with one entry for the pseudo host ``list-processor''
          or something similar.  This program is called by the program
          deliver and is not meant to be invoked by users directly.

          The list channel performs two  basic  services.   First,  it
          postpones   the  verification  of  the  list  addresses  and
          performs  the  (possibly  lengthy)   verification   in   the
          background  when  the  list channel resubmits the message to
          the  mail  system.   This  prevents  tying  up   a   network
          connection  or  a  user's  terminal  when  verifying  a long
          mailing list.  Second, the list channel will, under  special
          circumstances,  change the return address for the message to
          a generic  maintainer's  address.   The  return  address  is
          determined  by  first  taking  the destination address (e.g.
          ``largelist'') and seeing if there  is  an  address  in  the
          alias  file called ``largelist-request''.  If there is, then
          ``largelist-request'' is used as  the  return  address.   If
          that  was  not  found, the list channel checks to see if the
          destination address has a trailing  ``-outbound''.   If  so,
          this  is stripped and a ``-request'' is added and the lookup
          in  the  alias  file  is  made  a  second  time.    If   the
          ``-request''  address is found, then that address is used as
          the return address.  If no ``-request''  address  is  found,
          then  the  original  return  address  is  used (normally the
          address of the sender).

          To use the list channel to process a list, it  is  generally
          necessary  to  make three entries in the alias file(s).  Let
          us say that we wish to set up a  list  called  ``largelist''
          and  we  want this list to be processed by the list channel.
          We would need the following entries in the alias file:

                largelist:          largelist-outbound@list-processor
                largelist-outbound: </usr/mmdf/lists/largelist-file
                largelist-request:  maintainer

          The first line causes mail sent to ``largelist'' to be  sent
          through  the  list  processor,  readdressed  to ``largelist-
          outbound''.  The second line is what actually references the
          mailing  list  file  for  ``largelist''.   The third line is
          optional, and is used to  set  up  the  (informal)  standard
          maintenance  address.   This  -request  address, if present,
          will also be used by the list channel as the return  address
          for mail submitted to the list.


     See Also
          deliver(ADM), submit(ADM)


     Files
          <mmdf-table-directory>/aliases  -   to   find   list-request
          addresses


     (printed 2/15/90)                                  LIST(ADM)