uknet@ukc.ukc.ac.uk (Network Management) (04/10/88)
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Seminars by Dennis M Ritchie & Andrew G Hume
AT&T Bell Laboratories
Tuesday 12th April, 1988 from 15:00 to 16:30
City University London, Room A.537.C - Senate Suite
FROM: Sunil K. DAS , Computer Science Department
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The Computer Science Department of City University London is holding
two prestigious, academic seminars which will be given by visitors
from the Computer Science Research Centre of Bell Laboratories in
Murray Hill, New Jersey, USA. Entry will be by ticket only which
can be obtained by telephoning Mohammad Nejad-Sattary, on
01-253-4399 ext: 3726.
Interprocess Communication in the Ninth Edition Unix System
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Dennis M. Ritchie
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The stream mechanisms of the Eighth Edition Unix system combine with
its facilities for remote file systems to provide a natural and
general way to establish interprocess communication. In this design,
which became fully developed in the Ninth Edition system, the names at
which processes rendezvous are file system names.
By exploiting interprocess communication, we have simplified the
problems of intermachine communication. The tedious code for
establishing connections on various networks can be hidden in servers
instead of burdening either the operating system or the user's own
programs. For example, we use a single program for doing remote login
on TCP/IP networks like Ethernet, on our very different Datakit
network, and over ordinary telephone lines. It, and similar programs,
operate by calling a connection server, passing the desired address
and service, and receiving a descriptor ready for communication.
Mk : a successor to make
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Andrew G Hume
~~~~~~~~~~~~~
Mk is an efficient general tool for describing and maintaining
dependencies between files or programs. Mk is styled on, and largely
compatible with the UNIX tool make . The major advantages of mk
over make are executing recipes in parallel, using pattern-matching
metarules rather than suffix transformation rules, and deriving
dependencies by transitive closure on all rules. Mk runs anywhere
from 2 to 30 times faster than make.
The paper which appeared in the Summer 1987 Usenix Conference Proceedings
describes mk by means of an evolving example. Other sections summarise
the differences between mk and make and discuss the principles
underlying mk's design.
Biographical Notes
~~~~~~~~~~~~~~~~~~
The UNIX system has brought great honour to the primary contributors,
Ken Thompson and Dennis Ritchie, and has reflected respect upon many others
who have built on their foundation. Without the vision of Ken Thompson,
UNIX would not have come into existence; without the insight of Dennis Ritchie,
it would not have evolved into a polished presence; without the imagination of
Mike Lesk and popularising touch of Brian Kernighan, it would not have
acquired the extroverted personality that commands such widespread loyalty.
Dennis M Ritchie (USA), AT&T Bell Laboratories
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Ken Thompson began the construction of the UNIX system from the ground
up based on a file system model worked out with Dennis Ritchie and Rudd
H Canaday. Dennis, best known as the father of C, joined Ken very early
on. He contributed notions such as fork-exec and set-userid
programs. Jointly, they wrote the fc compiler for Fortran IV. The
first debugger db and the definitive ed were Dennis', as was
the radically new stream basis for IO in v8 and much networking software.
Datakit and streams made possible Peter Weinberger's network file system
and Dave Presotto's connections to diverse networks. As a result the research
machine is no longer identifiable; users can - and do - work on one or more
of two dozen computers simultaneously. With Steve Johnson, Dennis made UNIX
portable, moving the system to an Interdata machine (v7).
Andrew G Hume (Australia), AT&T Bell Laboratories
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Andrew wrote proof to put troff on your screen (v8), parts
of the UNIX Circuit Design System (v9), mk to supplant make ,
and a remote backup service (v9). His most recent research has
been to speed up the grep family of programs, as discussed in the
EUUG Conference Proceedings paper ``Grep Wars'' to be presented on the 15th
April, 1988 at the Queen Elizabeth II Centre, London. Sunil K Das is
the Programme and Conference Chairman.
We look forward to seeing you.
Yours sincerely, Sunil K. Das
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