IBM AIX

Fri Sep 2 01:19:45 AEST 1988

The AIX Family Definition Overview, published in July, includes a matrix
listing system calls, library routines and user commands.  For each item
there is an indication of whether it is present in the first release of
AIX PS/2, the 2.2.1 release of AIX/RT, the first release of AIX 370, the
AIX Family (some AIX products will have additional items not in the family),
POSIX, SVID and BSD 4.3.

I think that matrix answers most of the questions in the referenced article.

Here are the repostings:

From: sauer at auschs.UUCP (Charlie Sauer)
Newsgroups: comp.unix.wizards
Subject: AIX facts, history and status
Date: 9 Jun 88 23:14:21 GMT
Organization: IBM AES, Austin, TX
Keywords: AIX

Since a future version of AIX will be core technology for the OSF products,
I think it is useful to summarize publicly announced AIX facts and status.  I 
am speaking for AIX, not the OSF, and I am not going to talk about the 
unannounced plans for AIX.  Several of us in Austin have disclosed AIX 
technology in development to the OSF seed team, and I expect that OSF will 
announce OSF plans with respect to AIX technology when appropriate.

AIX on the RT is now in it's fifth release, known as AIX 2.2, which is 
officially available on June 24.  Another release on the RT (2.2.1) and 
AIX PS/2 are scheduled for September availability, and AIX/370 is scheduled 
for March availability.  

AIX development personnel participate actively in the POSIX committees, and
AIX is committed to POSIX compliance.

AIX was originally derived from SVR1 and SVR2.  We have endeavored 
to maintain the functionality in the BA sections of SVID at the SVR2 level. 
There are some incompatibilities, which I personally consider minor.

Evolutionary compatibility with BSD has been part of AIX development starting
with the initial release.  An abstract on 4.3 convergence is being posted 
separately.

AIX also includes many components from vendors, from other universities, and 
from IBM development and research. 

There is a recent overview paper on AIX[1], but I will list a few of the
areas where we have focused development and research effort:

   virtual memory management and mapped files.  The AIX/RT pager is derived
   from work originally done in the CP.R project at IBM Watson Research Center.

   services for managing "real time" devices and applications.

   optimizing compiler technology based on the 801 project at IBM Research[2]
   and related technology, e.g., the dynamic binding code used for device
   handlers.

   internationalization.

   integrating SNA and related communications products with Unix.

   distributed system support[3].

It is our plan that AIX be consistent in both interfaces and actual
source code base across the 386, RISC and 370 platforms.  (There are some
areas where consistency is not achievable due to hardware differences, e.g.,
IEEE floating point vs. 370 floating point. Given resource and schedule 
pragmatics, there will be functions not present in particular platforms in 
particular releases.)  The AIX Family Definition Overview, to be published
next month, summarizes the system call interfaces, library routines and 
commands which are common across the AIX Family.  This includes the BSD
compatibility described in the accompanying abstract, X11, NFS, Distributed
Services, TCP/IP, etc.

REFERENCES:

1. L.K. Loucks and C.H. Sauer, "Advanced Interactive Executive (AIX) Operating
   System Overview," IBM Systems Journal 26, 4 (1987).

2. M. Auslander and M.E. Hopkins, "An Overview of the PL.8 Compiler," Proc. of
   the SIGPLAN '82 Symposium on Compiler Writing, Boston, MA.

3. C.H. Sauer, D.W. Johnson, L.K. Loucks, A.A. Shaheen-Gouda and T.A.
   Smith, "RT PC Distributed Services Overview," Operating Systems
   Review 21, 3 (July 1987) pp. 18-29.

- -------- 

From: sauer at auschs.UUCP (Charlie Sauer)
Newsgroups: comp.unix.wizards
Subject: Convergence of AIX and 4.3BSD
Date: 9 Jun 88 23:19:33 GMT
Organization: IBM AES, Austin, TX
Keywords: AIX BSD 4.3

Following is an abstract of a paper we plan to write:

CONVERGENCE OF AIX AND 4.3BSD

   Charles H. Sauer (1)
   Kathy A. Bohrer (1)
   Tom Lang (1)
   Conrad Minshall (2)
   Gary L. Owens (1)
   Kris Solem (3)
   Bruce J. Walker (4)

                            (1) IBM Advanced Engineering Systems, Austin, TX
                            (2) IBM Technical Computing Systems, Palo Alto, CA
                            (3) formerly IBM Technical Computing Systems, 
                                now MIPS Computer Systems
                            (4) LOCUS Computing Corporation, Santa Monica, CA        

AIX started with a number of BSD features, e.g., 4.2 signals and concurrent
groups[1]. Over time, additional features associated with BSD, such as pty's,
select, sockets and sendmail have been added, with new features being added in
each release.  Based on this experience, and experience with 4.3/RT, it 
appeared that fairly strict BSD compatibility could be achieved, and the 
authors and others set out to define such compatibility.

This paper describes methodology and decisions made in defining a convergence
of BSD 4.3 and AIX.  This convergence will be reflected in the AIX Family
products and the version of AIX to be provided to the Open Software Foundation.

Among the goals of the work were

   POSIX compliance

   Base SVID functionality at the SVR2 level

   Compatibility with documented and undocumented BSD 4.3 characteristics
   and interfaces

   Compatibility with existing AIX interfaces

   Completeness - providing essentially all BSD 4.3 functions

   Minimal redundancy - except in a few cases where redundancy seemed
   inescapable, conflicts were resolved to provide a single merged
   definition of system call, library and command interfaces.  Users
   and programmers should normally not be conscious of the historical 
   basis of the converged interface.

   Portability - minimizing porting effort for users and applications
   associated with existing AIX and 4.3 implementations.

In addition, many of the system administration facilities were addressed in
a converged manner.  The effectiveness of the approach is demonstrated by
success with test suites originally designed for AIX/RT and 4.3/RT prior
to the convergence effort.

ACKNOWLEGEMENT

Many others contributed to this work, including, from IBM Advanced Engineering
Systems: Rob Cordell, Jim DeGroot, Patrick Goal, Carolyn Greene, Larry Loucks,
Jim Mott, Mike Schmidt, Doug Steves and Ken Witte, from IBM Data Systems 
Division, Johnny Barnes and Heinz Graalfs, from IBM Research, Marc Auslander,
from IBM Technical Computing Systems, Larry Breed, Bruce Campbell, Sanjay 
Challani, Tu-An Cheng, Tri Ha, Chirag Jain, Jason Kosol, Betty Lee, Derrick Mar,
Teri McConnell, Lisa Repka (now with Evans and Sutherland), Laura Richardson 
and Dave Zittin (now with Sun Microsystems), from Lachman Associates 
Incorporated, Jim Norris, from LOCUS Computing Corporation, Bob Peterson, 
and from Sunday and Associates, Roy Gordon.

REFERENCE:

1. L.K. Loucks and C.H. Sauer, "Advanced Interactive Executive (AIX) Operating
   System Overview," IBM Systems Journal 26, 4 (1987).
-- 
Charlie Sauer   IBM AES/ESD, D75/802     uucp: cs.utexas.edu!ibmaus!sauer
                11400 Burnet Road       csnet: ibmaus!sauer at CS.UTEXAS.EDU
                Austin, Texas 78758    aesnet: sauer at auschs  
                (512) 823-3692           vnet: SAUER at AUSVM6