Date: Tue, 22 Sep 1998 23:21:58 -0400
From: Peter Radcliffe <pir@pir.net>

Philip Hazel <ph10@cus.cam.ac.uk> probably said:
> On Fri, 18 Sep 1998, Tabor J. Wells wrote:
> > One of our customers is looking for us to support addresses of the form
> > username+extension@domain.com, primarily for use with procmail.

> Look up the "prefix" and "suffix" options of directors. A smartuser 
> director with options along the lines of
> 
>   suffix = +extension
>   new_address = some kind of lookup to get the rewrite, and then 
>                 manipulation involving the use of $local_part_suffix
>                 to put the extension back. Depending on your lookup,
>                 could be messy...

Thats what I was doing before I saw this ;)
If this isn't clear and you want an explanation, ask ...

Note to Tabor: I added qualify_preserve_domain to the virtual director.
This is not what you have now and will break things, you'll have to remove
it and alter the virtual suffix as it says.

# macros

EBASE = /usr/local/etc/exim
DSUFFIX = -
# DSUFFIX = +
DBEXT = .db
#DBEXT = 

## transports

# delivery by procmail, local users with .procmailrc files only
procmail_pipe:
  driver = pipe
  delivery_date_add = true
  envelope_to_add = true
  return_path_add = true
  path = "/usr/local/bin:/usr/bin"
  command = "procmail -a ${substr_1:${local_part_suffix}} -d ${local_part}"
  from_hack
  user = ${local_part}


## directors

# deal with virtual domains - just for virtual domains, look them up
virtual:
  driver = aliasfile
  domains = dbm;EBASE/dbm/virtualDBEXT
  file = EBASE/domains/${lc:${length_1:${domain}}/${domain}}DBEXT
  search_type = dbm*
  forbid_file
  forbid_pipe
  qualify_preserve_domain


# if the virtual domain has no postmaster or root alias, throw them at
# the default domain
virtualpostmaster:
  driver = smartuser
  domains = dbm;EBASE/dbm/virtualDBEXT
  local_parts = "postmaster:root"
  new_address = ${local_part}@${qualify_recipient}


# and if there is a -something suffix, send it to the right place
virtualsuffix:
  driver = smartuser
  domains = dbm;EBASE/dbm/virtualDBEXT
  no_more
  suffix = DSUFFIX*
# if you want this to not do qualify_preserve_domain replace ' {$domain} '
# with ' {$qualify_recipient} ' in the 7th line.
  new_address = "\
    ${lookup{$local_part} dbm \
      {EBASE/domains/${lc:${length_1:${domain}}/${domain}}DBEXT} \
      {\
        ${if !match {$value}{^:(defer|fail|blackhole|include):} \
          {${local_part:$value}${local_part_suffix}@\
           ${if eq {${domain:$value}} {} {$domain} {${domain:$value}}}}\
        fail}\
      }\
    fail}"

.
.
.

userforward:
  driver = forwardfile
  no_verify
  check_ancestor
  file = .forward${local_part_suffix}
  filter
  suffix = DSUFFIX*
  suffix_optional


# Use procmail only if a ~/.procmailrc file exists, and procmail exists.
# If sending to a username-suffix and $HOME/.forward-suffix exists,
# its valid.
procmail:
  driver = localuser
  transport = procmail_pipe
  require_files = "${local_part}:${home}/.procmailrc:+/usr/local/bin/procmail"
  suffix = DSUFFIX*
  suffix_optional
  
# I realised that this might pass things to procmail when you have a .forward
# file and expect it not to happen (if .forward and .procmailrc exist user-foo
# will still get passed to procmail).
# To stop this you can change the above to use:
 
  require_files = "${local_part}:${home}/.procmailrc:+/usr/local/bin/procmail\
                    :!${home}/.forward"