|
MULTICS MULTICS操作系統 MULTICS操作系統 /muhl'tiks/ MULTiplexed Information and
Computing Service. A {time-sharing} {operating system}
co-designed by a consortium including {MIT}, {GE} and {Bell
Laboratories} as a successor to MIT's {CTSS}. The system
design was presented in a special session of the 1965 Fall
Joint Computer Conference and was planned to be operational in
two years. It was finally made available in 1969, and took
several more years to achieve respectable performance and
stability.
Multics was very innovative for its time - among other things,
it was the first major OS to run on a {symmetric
multiprocessor}; provided a {hierarchical file system} with
{access control} on individual files; mapped files into a
paged, segmented {virtual memory}; was written in a
{high-level language} ({PL/I}); and provided dynamic
inter-procedure linkage and memory (file) sharing as the
default mode of operation. Multics was the only
general-purpose system to be awarded a B2 {security rating} by
the {NSA}.
Bell Labs left the development effort in 1969. {Honeywell}
commercialised Multics in 1972 after buying out GE's computer
group, but it was never very successful: at its peak in the
1980s, there were between 75 and 100 Multics sites, each a
multi-million dollar {mainframe}.
One of the former Multics developers from Bell Labs was {Ken
Thompson}, a circumstance which led directly to the birth of
{Unix}. For this and other reasons, aspects of the Multics
design remain a topic of occasional debate among hackers. See
also {brain-damaged} and {GCOS}.
MIT ended its development association with Multics in 1977.
Honeywell sold its computer business to {Bull} in the mid
1980s, and development on Multics was stopped in 1988 when
Bull scrapped a Boston proposal to port Multics to a
{platform} derived from the {DPS-6}.
A few Multics sites are still in use as late as 1996.
The last Multics system running, the Canadian Department of
National Defence Multics site in Halifax, Nova Scotia, Canada,
shut down on 2000-10-30 at 17:08 UTC.
The {Jargon file} 3.0.0 claims that on some versions of
Multics one was required to enter a password to log out but
James J. Lippard , who was a Multics
developer in Phoenix, believes this to be an {urban legend}.
He never heard of a version of Multics which required a
password to logout. Tom Van Vleck
agrees. He suggests that some user may have implemented a
'terminal locking' program that required a password before one
could type anything, including logout.
{(http://multicians.org/)}.
{Usenet} newsgroup: {news:alt.os.multics}.
[{Jargon File}]
(2002-04-12)
MULTiplexed Information and Computing Service ( OS, MIT, Bell) Multics: / muhl´ tiks/, n. [ from “ MULTiplexed Information and Computing Service”] An early timesharing operating system co- designed by a consortium including MIT, GE, and Bell Laboratories as a successor to CTSS. The design was first presented in 1965, planned for operation in 1967, first operational in 1969, and took several more years to achieve respectable performance and stability. Multics was very innovative for its time — among other things, it provided a hierarchical file system with access control on individual files and introduced the idea of treating all devices uniformly as special files. It was also the first OS to run on a symmetric multiprocessor, and the only general- purpose system to be awarded a B2 security rating by the NSA ( see Orange Book). Bell Labs left the development effort in 1969 after judging that second- system effect had bloated Multics to the point of practical unusability. Honeywell commercialized Multics in 1972 after buying out GE' s computer group, but it was never very successful: at its peak in the 1980s, there were between 75 and 100 Multics sites, each a multi- million dollar mainframe. One of the former Multics developers from Bell Labs was Ken Thompson, and Unix deliberately carried through and extended many of Multics' design ideas; indeed, Thompson described the very name ‘ Unix’ as “ a weak pun on Multics”. For this and other reasons, aspects of the Multics design remain a topic of occasional debate among hackers. See also brain- damaged and GCOS. MIT ended its development association with Multics in 1977. Honeywell sold its computer business to Bull in the mid 80s, and development on Multics was stopped in 1988. Four Multics sites were known to be still in use as late as 1998, but the last one ( a Canadian military site) was decommissioned in November 2000. There is a Multics page at http:// www. stratus. com/ pub/ vos/ multics/ tvv/ multics. html.
|
安裝中文字典英文字典查詢工具!
中文字典英文字典工具:
英文字典中文字典相關資料:
|