IAS MAIL UTILITY

                               R. N. Stillwell
                        Institute for Lipid Research
                         Baylor College of Medicine
                            Houston, Texas 77030
                                713-799-4721


                             GENERAL DESCRIPTION

     IAS MAIL  is a pair of IAS programs  that allow users  to send each other
messages.   It is modeled generally on ARC MAIL, developed by William Korendyk
and Mark Johnson, and available on the RSX/IAS SIG tapes.   Rather than try to
modify the  Macro code of  ARC MAIL  to use the  quite  different  system data
structures of IAS, I have written IAS MAIL as a new set of programs, primarily
in Flecs (a structured Fortran).

     IAS MAIL has three components: a timesharing task (MAIL) that handles all
of the user  interaction  in  sending  or  receiving  mail;  a real-time  task
(POSTMAN)  that notifies the recipient  that he has mail;  and a system global
area (MAICOM) that provides communication between the two tasks.  A third task
(WHODID)  is also used  to create  a user  directory;  this  is  primarily  an
accounting  task,  and is  used at ILR  by the System  Manager  as part of the
monthly accounting procedure.

     IAS MAIL  accesses three  directories  on SY0: besides the user's default
directory:  [1,100] for WHODID.LST, the user directory; [10,0] for the mailbox
files; and [10,3] for public mailing lists. Account [10,0] must be set up with
protection  (WO:RWE).   Account [10,3] may be  protected  (WO:RWE) if any user
may set up a public mailing list, or (WO:R) if only system users may.


                       INSTALLATION NOTES

     The  DCL command  file  MAIL.CMD  will  handle  the  entire  installation
procedure if the following are true:

     o  The installer is logged in as a privileged user.

     o  The installer's default disk = SY0: = LB0:

     o  Flecs is installed with Mark Lewis's DCL interface.

     o  There is a system library called F25RES (containing Fortran v2.5 OTS).

You will probably need to list and edit the various command files to suit your
configuration.  WHODID.FLX  summarizes users  by major  categories  (groups of
UICs)  for our record-keeping  purposes.  You should substitute your own cate-
gories or remove that part of the code; it is not necessary for MAIL.

When the MAIL system has been built and tested, edit your startup command file
to schedule the  POSTMAN.  If you have  plenty of memory,  FIX him (we have an
11/45 and can't afford the space).


                     BUGS, CROCKS AND KLUDGES

MAIL and POSTMAN do not recognize a user logged in at TT0:

POSTMAN  (installed as POSTMN)  runs every  few seconds  (e.g. 5) to check for
users  newly logged in or out.  If he finds a new login, he does a file lookup
to see if the user  has anything in his mailbox.  If you have memory to spare,
you can save some of this overhead by fixing POSTMN.

It  might  be better  if  MAICOM  contained  a  list  of  non-empty  mailboxes
(maintained  by MAIL).   Then  POSTMAN  wouldn't have to do a file lookup, and
would be much smaller and faster.

Using  WHODID.LST  as a  user directory  is not  very elegant,  but it  allows
[1,100]PDSUPF.DAT to be protected against snoopers (passwords are not securely
encrypted).

The type-a-letter-at-the-terminal feature of MAIL would be nicer if it invoked
an editor.

Mailing lists are restricted to 80 characters.  This is ridiculous.

If you try  to reply to a letter you have written to yourself, MAIL bombs out.
Can you blame it?