03/09/88  mailbox acls

In MR12.1, the message segment primitives were changed to enforce
some new restrictions on allowable mailbox and message segment
extended ACLs.  Specifically:
  1. All ACL entries containing the "r" mode must also contain "s".
  2. All ACL entries containing either "w" or "u" mode must also
     contain "a".

Since both delete_acl and set_acl always call hcs_$replace_acl,
any segments with existing ACL entries which violate the new
restrictions cannot have their ACLs changed unless these old
inconsistent ACLs are changed at the same time.


For example, an existing mailbox with the ACL:

   adrow   GDixon.SysMaint.*
   arow    Lippard.Multics.*
   aow     *.*.*

cannot be changed unless the entries for GDixon.SysMaint and
Lippard.Multics are changed at the same time.  This may be
accomplished in several ways.  With set_acl, you must specify new
modes for each of the bad ACL entries in a single command line:

   sa foo.mbx adrosw GDixon.SysMaint arosw Lippard.Multics

With delete_acl, you must delete all of the bad ACL entries in a
single command line:

   da foo.mbx GDixon.SysMaint Lippard.Multics

If there are a large number of bad ACL entries on a segment, you may
wish to delete them all and start over.  This may be easily
accomplished with the command:

   da foo.mbx ..


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Historical Background

This edition of the Multics software materials and documentation is provided and donated
to Massachusetts Institute of Technology by Group BULL including BULL HN Information Systems Inc. 
as a contribution to computer science knowledge.  
This donation is made also to give evidence of the common contributions of Massachusetts Institute of Technology,
Bell Laboratories, General Electric, Honeywell Information Systems Inc., Honeywell BULL Inc., Groupe BULL
and BULL HN Information Systems Inc. to the development of this operating system. 
Multics development was initiated by Massachusetts Institute of Technology Project MAC (1963-1970),
renamed the MIT Laboratory for Computer Science and Artificial Intelligence in the mid 1970s, under the leadership
of Professor Fernando Jose Corbato. Users consider that Multics provided the best software architecture 
for managing computer hardware properly and for executing programs. Many subsequent operating systems 
incorporated Multics principles.
Multics was distributed in 1975 to 2000 by Group Bull in Europe , and in the U.S. by Bull HN Information Systems Inc., 
as successor in interest by change in name only to Honeywell Bull Inc. and Honeywell Information Systems Inc. .

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Permission to use, copy, modify, and distribute these programs and their documentation for any purpose and without
fee is hereby granted,provided that the below copyright notice and historical background appear in all copies
and that both the copyright notice and historical background and this permission notice appear in supporting
documentation, and that the names of MIT, HIS, BULL or BULL HN not be used in advertising or publicity pertaining
to distribution of the programs without specific prior written permission.
    Copyright 1972 by Massachusetts Institute of Technology and Honeywell Information Systems Inc.
    Copyright 2006 by BULL HN Information Systems Inc.
    Copyright 2006 by Bull SAS
    All Rights Reserved