Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!uwm.edu!rutgers!mcdchg!chinet!les
From: les@chinet.chi.il.us (Leslie Mikesell)
Newsgroups: comp.mail.uucp
Subject: Re: differences between smail 2.5 and smail 3.x
Message-ID: <1990Jul7.210214.3130@chinet.chi.il.us>
Date: 7 Jul 90 21:02:14 GMT
References: <2690C7F4.A40@tct.uucp> <1990Jul4.221134.15621@tolerant.com> <:MG4LEG@xds13.ferranti.com>
Organization: Chinet - Public Access UNIX
Lines: 30

In article <:MG4LEG@xds13.ferranti.com> peter@ficc.ferranti.com (Peter da Silva) writes:
>Just what are the differences between smail 2.5 and 3.x?

Smail 2.5 does simple aliasing and path routing, decides which addresses are
local and remote, then hands everything off to another program to deliver.
Smail 3.1 also handles the delivery to files, other programs, or via SMTP.
It is much more complex, mostly due to the design which provides generalized
low-level routines for database lookups (linear, binary search, and dbm)
and delivery methods (append-to-file, pipe, smtp, etc) and allows either
compiled-in defaults or runtime configuration files to specify the details
of when and how to use them.
The default configuration will allow you to specify multiple names to
be accepted as the local host, and allows aliases to expand to the
same thing as the address that produced it, in which case it moves on
to the next step in the delivery.  This lets you share an alias file
file among several machines (the expansion to user@local-machine is accepted),
and you can include your own name in a .forward file along with other
addresses (the next step in delivery would be to your mailbox).  Expansions
that are different from the address that produces them are handled from
the top and thus may refer to other aliases or remote addresses to be routed.
Files and pipes to programs may be specified in the alias and forward files
with an assortment of security options to control execution.  There
are provisions for mailing lists and delivery may be configured for
foreground, background, or queued (a scheduled or daemon process delivers
later).  It appears to be able to be interrupted in the middle of delivery
to a list and be restarted later without duplication or omissions, something
that would be difficult to do with multi-process mail handling.

Les Mikesell
  les@chinet.chi.il.us