Change Notes for things later than this file:

	See file  ChangeLog

Change Notes for 2.2:

	Rayan didn't write them ?

Change notes for 2.1:

Configuration:

The old "transport" method in the configuration is now called "routes".
At the same time, the MAILSHARE/db/hosts.transport file was renamed
MAILSHARE/db/routes.

Renamed the MAILSHARE/db/localdelivery file to MAILSHARE/db/localnames.

Added the MAILSHARE/db/otherservers file.  In a multi-MTA cluster, it is
intended to hold the names of all the *other* MTA hosts.

The BITNET handling was improved a bit.

The login to uid and uid to login map caches are flushed after each message.

The (now) "routes" file can take a new directive: delay!<seconds>.
This will put the address in a hold queue with an appropriate timeout set.

The logging was rationalized.  An awk script to process the router log
(and produce something that can be turned into bills, for illustration only
of course :-), is in utils/zmstats.

The PUNTHOST and SMARTHOST variables can be set (e.g. in zmailer.conf) to
declare a host to forward to if a local or remote (respectively) address
is unresolvable.


Router:

Decreased threshold on Received: headers from 100 to 50

Added new databases (actually, made them visible):

	pwuid		maps uid to login name (mnemonic: getpwuid)
	pwnam		maps login name to uid (mnemonic: getpwnam)
	headers		maps header field name to descriptor

Added new "header" database type, used for an internal database which
configures the RFC822 header parser.  This type is unlikely to be used
in any other context.  It is used to define/select/deselect the non-essential
RFC822 headers to be parsed and interpreted by the router.

Added new "squirrel" builtin function.  It sets the kinds of events that
cause a message to be copied into the POSTOFFICE/postman directory.
The list of events are: breakin, badheader, illheader, nochannel, nosender.
The latter three almost never happen.  Usage is "squirrel { [-]<event> }"
to enable/disable the flags associated with the events.

Test-and-Lock each mail message before the router starts processing it, and
unlock it after the router is done.  This allows concurrent routers.

Added an "envelopeinfo" global variable in the configuration file, defined
(by the builtin rfc822 function) as a property list of the following elements:

	file		message file name
	message-id	the message-id
	uid		the user id of the owner of the message file
	gid		the group id of the owner of the message file
	size		the message size (header + body) in bytes
	headersize	the message header size in bytes
	bodysize	the message body size in bytes
	now		the time the router started processing the message
			(in seconds sinze epoch)
	delay		the number of seconds the message had been queued
	resent		"yes" or "no" indicating whether Resent- headers exist
	trusted		"yes" or "no" indicating whether file owner is trusted

furthermore every envelope header without address semantics will be added
to the list, typically:

	with		RFC822 Received header "with" value.
	via		RFC822 Received header "via" value.
	rcvdfrom	The host of the last MTA to touch the message.


Scheduler:

Fixed some systemic problems in the scheduler algorithms; it was possible
to run into a situation where some set of messages would block another
set of messages.  This was fixed by imposing a fair roundrobin scheme
for randomly selected-for-retry messages that are deferred due to resource
starvation.  In other words, the randomness is enforced.


Transport Agents:

The "mailbox" transport agent program takes a "-l file" command line argument.
All its deliveries will be logged to that file.

Improved the logging done by the SMTP client program.


SMTP Server:

The "smtpserver" program takes a "-l file" command line argument.
All incoming SMTP conversations will be logged to that file.

Added the 8-bit SMTP extension verbs as synonyms for the 7-bit ones.  I
think this is sufficient for full conformance with the to-be-RFC proposal.
No translation capability is provided, as yet.

Dotted quads are recognized as a valid parameter type for the HELO command.

Superfluous <'s and >'s on addresses are detected (synchronously) and
the command refused.

--
Change notes for 2.0:

"I threw away all the old bugs and created a whole new set"

This implementation doesn't retain much code from the 1.4 release.
The major changes are the router configuration language (1.5 years in
development), improvements in the scheduler (1 week), and rationalization
of transport agent code (2 days).  There is a new system configuration
mechanism (the hostenv directory) and associated changes in the code.

--
Change notes for 1.4:

The following differences will be apparent from the 1.3 release:

- There are now three logical places for ZMailer files:

	POSTOFFICE	spool
	MAILBIN		binaries/programs
	MAILSHARE	configurations/databases/text/zmailer

  This is in response to the distinction between the architecture-dependent
  and -independent files, being made in SunOS 4.0 and presumably future UCB,
  DEC, Sun, and ATT releases.

- The $POSTOFFICE/forms directory has been moved to $MAILSHARE/forms.
  Remember to do this manually, using or merging in the contents of proto/forms.

- The scheduler configuration file has been renamed "scheduler.cf" (it
  was "scheduler.cntl").

- The $POSTOFFICE/.{router,scheduler}.pid files are now .pid.{router,scheduler}
  and a .pid.smtpserver has been added.

- There are manual pages for the zmailer script and the mailq program.
  The manual pages are not installed automatically, you may want to do it
  yourself.