On behalf of Bellcore, I am happy to announce the availability of the
"metamail" software to the email community. This package, which is
available free of charge for unlimited use by anyone for any purpose, is
offered in the hope of making multimedia mail more widespread.
OVERVIEW
The basic idea of "multimedia" electronic mail is to extend email as we
now know it to include many other types of data beyond plain English
text. In particular, there is no reason, in principle, why email should
not include text in any of the world's languages and character sets, nor
why email should not include pictures, sounds, animations, active
spreadsheets, or any other kind of data that can be stored on a computer.
In recent years, various research systems and even some commercial
products have extended email to include some or all of these
capabilities. Until recently, however, none of them worked together,
and all of them required whole communities of users to abandon their old
tools en masse in favor of the new tools of a single software vendor.
Recent developments have the promise of changing all of that. There is
a new proposed standard for the format of multimedia mail, which would
make software from different vendors able to work together smoothly with
multimedia mail, as they do now with plain text mail. The software
being announced here implements that proposed standard, but takes it a
step further by incorporating it into the existing tools with which
people read mail today, allowing multimedia mail to be adopted in an
evolutionary rather than a revolutionary fashion.
DETAILS
Metamail is a package that can be used to convert virtually ANY
mail-reading program on UNIX into a multimedia mail-reading program. It
is an extermely generic implementation of MIME (Multipurpose Internet
Mail Extensions), the proposed standard for multimedia mail formats on
the Internet. The implementation is extremely flexible and extensible,
using a "mailcap" file mechanism for adding support for new data formats
when sent through the mail. At a heterogeneous site where many mail
readers are in use, the mailcap mechanism can be used to extend them all
to support new types of multimedia mail by a single addition to a
mailcap file.
The core of the package is a mechanism that allows the easy
configuration of mail readers to call external "viewers" for different
types of mail. However, beyond this core mechanism, the distribution
includes viewers for a number of mail types defined by the MIME
standard, so that it is useful immediately and without any special
site-specific customization or extension. Types with built-in support
in the metamail distribution include:
1. Plain US ASCII (i.e., English) text, of course.
2. Plain text in the ISO-8859-8 (Hebrew/English) character set.
3. Richtext (multifont formatted text, termcap-oriented viewer)
4. Image formats (using the xloadimage program under X11)
5. Audio (initial "viewer" for SPARCstations)
6. Multipart mail, combining several other types
7. Multipart/alternative mail, offering data in multiple formats.
8. Encapsulated messages
9. Partial & external messages (for large data objects)
10. Arbitrary (untyped) binary data
Other media types and character sets may be easily supported with the
mailcap mechanism, using the provided types as examples/templates. The
metamail software also provides rudimentary support for the use of
non-ASCII characters in certain mail headers, as described by a
companion document to the proposed MIME standard.
The metamail distribution comes complete with a small patch for each of
over a dozen popular mail reading programs, including Berkeley mail, mh,
Elm, Xmh, Xmail, Mailtool, Emacs Rmail, Emacs VM, Andrew, and others.
Crafting a patch for additional mail readers is relatively
straightforward.
In order to build the metamail software, a single "make" command
followed by a relatively short compilation will suffice. Patching your
mail reader is somewhat harder, but can usually be accomplished in less
than an hour if you have the sources at hand. The experience of beta
testers is that the metamail package can easily be used to get
multimedia mail working with your existing mail readers in less than
half a day.
AVAILABILITY
To retrieve the file, use anonymous ftp to the machine
thumper.bellcore.com (Internet address 128.96.41.1). Type "cd pub/nsb".
In that directory, you will find:
1. mm.tar.Z -- this is a compressed tar file containing the entire
metamail distribution. Uncompress it, untar it, and read the top-level
"README" file for further instructions. Strictly speaking, this is the
only thing you really need to retrieve.
2. A subdirectory called "samples". Except for the README file, each
file in this directory is a sample MIME-format message, which can be
used to test your metamail installation.
3. BodyFormats.{ps,txt,ex} -- a copy (in PostScript/text/Andrew format)
of the latest draft of the MIME proposed standard. This document is
also available as an Internet Draft.
4. Configuration.{ps,txt,ex} -- a copy (in PostScript/text/Andrew
format) of the latest draft of the Internet informational RFC describing
the mailcap file format. This document is also available as an Internet
Draft.
A new mailing list has been set up for disucssion of the metamail
software and related issues. The mailing list is
INFO-MM(_at_)thumper(_dot_)bellcore(_dot_)com(_dot_) Requests to join the list
should be
directed to INFO-MM-REQUEST(_at_)thumper(_dot_)bellcore(_dot_)com(_dot_)
Please feel free to recirculate this announcement as widely as possible.
-- Nathaniel S. Borenstein <nsb(_at_)bellcore(_dot_)com>
Member of Technical Staff, Bellcore