FILTER(1L)          USENET Community Trust(Elm Version 2.3)          FILTER(1L)


NAME
      filter - filter incoming messages before adding to mailbox

SYNOPSIS
      filter [-v] [-o output]
      filter [-n]
      filter [-r] [-o output]
      filter [-c] [-s] [-o output]
      filter [-c] [-S] [-o output]

DESCRIPTION
      Filter is a sophisticated program that allows incoming mail to be
      filtered against a wide set of criteria.  The format for the rules,
      located in $HOME/.elm/filter-rules, is;

              rule  ::=  if  (expression)  then  action

      where expression is:

              expression  ::=  {  not  }  condition  expr2

              expr2  ::=  NULL  |  and  condition  expr2

              condition  ::=  field  relationship  value
                         ::=  lines  relop  numvalue
      or                 ::=  always

      These further break down as:

              field  ::=  from  |  subject  |  to  |  lines

              relationship  ::=  =  |  !=

              relop  ::=  =  |  !=  |  <  |  >  |  <=  |  >=

              value  ::=  any  quoted  string

              numvalue  ::=  any  integer  value

      Action can be any of:

              delete
              save  foldername
              savecopy foldername
              execute  command
              forward  address
              leave

      For further information about the rules language, please see The Elm
      Filter Guide.

      The flags the filter program understands are;


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FILTER(1L)          USENET Community Trust(Elm Version 2.3)          FILTER(1L)


      -c        Clear logs.  If this flag is used, the log files will be
                removed after being summarized by either "-s" or "-S" (see
                below).

      -n        Not really.  Output what would happen if given message from
                standard input, but don't actually do anything with it.

      -o file   Redirect all log messages to the specified file or device.
                (This is added to more gracefully deal with changes in the file
                system (since sendmail is quite picky about modes of files
                being redirected into.))

      -r        Rules.  List the rules currently being used.

      -s        Summarize.  List a summary of the message filtered log.

      -S        This is the same as `-s' but includes message-by-message
                information additionally.

      -v        Verbose.  Give output on standard out for each message
                filtered.  Useful to have redirected to ``/dev/console'' and
                such.  (see -o too).

AUTHOR
      Dave Taylor, Hewlett-Packard Laboratories.

FILES
      $HOME/.elm/filter-rules     The ruleset for the users filter
      $HOME/.elm/filterlog        A log of what has been done
      $HOME/.elm/filtersum        A summary of what has been done
      /etc/passwd             Used to get users home directory

SEE ALSO
      The Elm Filter Guide, by Dave Taylor.
      readmsg(1L), elm(1L), mail(1), mailx(1), sendmail(1,8)

COMMENTS
      Not real smart about pattern matching.

BUG REPORTS TO
      Syd Weinstein     elm@DSI.COM (dsinc!elm)

COPYRIGHTS
      © Copyright 1986, 1987 by Dave Taylor
      © Copyright 1988, 1989, 1990 by The USENET Community Trust









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