.fin
.all
     All "segments" and "directories" on Multics contain lists that indicate
who can use them.  These lists are called access control lists (or ACLs for
short).  By adding and erasing users' names from the ACLs of your segments and
directories, you can control who uses them.  This is an important feature of
Multics' security system.

     On segments there are three types of access:
.fif

r -- allows a user to read the segment
w -- allows a user to change or write in the segment
e -- allows a user to execute the segment if it is a program

     On directories there are also three types of access:

s -- allows a user to see the attributes of segments in the directory
m -- allows a user to modify attributes of segments in the directory
a -- allows a user to create, copy, or move segments in the directory
.fin

     In order to use a segment, a user must have appropriate access to both
the segment and the directory it is contained in.

     The names on an ACL have three parts:  the user's name and project (e.g.,
Smith.Mktg) and a component called an instance tag, which is usually denoted
by an asterisk (e.g., Smith.Mktg.*).  The asterisk means that whatever
instance tag a user has will be given access.  An asterisk can also be used in
the name and project components; it means that any name or any project will be
given access.

     The "commands" you use to maintain ACLs are: list_acl, set_acl, and
delete_acl.  To try these out and to see what an ACL looks like, go to
"command level" by pressing function key F2.  Once there type the list_acl
command without arguments to see the ACL on your working directory.  To see
the ACL of a segment, supply the segment's name as the "pathname" "argument"
to list_acl.  Before experimenting with set_acl or delete_acl, use the help
command to see exactly how to invoke them.


                                          -----------------------------------------------------------


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. .

                                          -----------------------------------------------------------

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