PDP-10 references in JARGON.TXT
Table of Contents
The original JARGON.TXT file was maintained in three locations back in
the days of the ARPANET. It was AIWORD.RF[UP,DOC] at SAIL (Stanford A.I.
Lab) and GLS;JARGON at MIT-MC and MIT-AI. A snapshot of that file
taken 14-Nov-1982 was online at
ftp://mc.lcs.mit.edu/its/ai/humor/jargon.68.Z (it is 43K, uncompresses
to 87K). [Archive offline, Jan 2001.]
I'm not sure exactly which version of JARGON was used when Guy L. Steele
published "The Hacker's Dictionary".
After Eric Raymond published "The New Hacker's Dictionary", the JARGON file
grew to 1.1 megabytes but the file hasn't been the same; it has lost a
lot of its hacker nature.
http://wiretap.spies.com/ftp.items/Library/Classic/jargon.txt
has "version 2.9.10 - 16 Jul 1992" in ASCII format.
http://fount.journalism.wisc.edu/jargon/Jargon.html
has "version 3.0.0 - 27 Jul 1993" in HTML format.
This was found at
ftp://sunsite.unc.edu/pub/academic/computer-science/history/pdp-10/docs
in the file "pdp10.song". Author unknown.
Oh Lord won't you buy me a PDP-10
My friends all hack Vaxen; I must make amends
Hacked hard all my lifetime, no help from my friends
So Lord, won't you buy me a PDP-10
Oh Lord won't you buy me an RM-03
Faster disk access is trying to find me
I wait for Disk Ready each afternoon 'till 3
So Lord, won't you buy me an RM-03
Oh Lord won't you buy me a disk pack so round
I'm counting on you, Lord, please don't let me down
God, I need a scratch pack; there's none to be found
So Lord won't you buy me a disk pack so round.
/ad'vent/ n. The prototypical computer adventure game, first
implemented on the {PDP-10} by Will Crowther as an attempt at
computer-refereed fantasy gaming, and expanded into a
puzzle-oriented game by Don Woods. Now better known as Adventure,
but the {{TOPS-10}} operating system permitted only 6-letter
filenames. See also {vadding}.
This game defined the terse, dryly humorous style now expected in
text adventure games, and popularized several tag lines that have
become fixtures of hacker-speak: "A huge green fierce snake bars
the way!" "I see no X here" (for some noun X). "You are in a
maze of twisty little passages, all alike." "You are in a little
maze of twisty passages, all different." The `magic words'
{xyzzy} and {plugh} also derive from this game.
Crowther, by the way, participated in the exploration of the
Mammoth & Flint Ridge cave system; it actually *has* a
`Colossal Cave' and a `Bedquilt' as in the game, and the `Y2' that
also turns up is cavers' jargon for a map reference to a secondary
entrance.
From Bill Bourn (30-Oct-95):
I never got to play Adventure myself because I translated that
36-bit fortran to PL/1 for VM/CMS. It wasn't an easy fit on the
32-bit IBM mainframe. I did get a kick out of watching my "testing"
cadre stumble around the Colossal Cave though.
1. /aws/ (East Coast), /ay-os/ (West Coast) [based on a
PDP-10 increment instruction] vt.,obs. To increase the amount of
something. "AOS the campfire." Usage: considered silly, and now
obsolete. Now largely supplanted by {bump}. See {SOS}.
Historical note: AOS in sense 1 was the name of a {PDP-10}
instruction that took any memory location in the computer and added
1 to it; AOS meant `Add One and do not Skip'. Why, you may ask,
does the `S' stand for `do not Skip' rather than for `Skip'? Ah,
here was a beloved piece of PDP-10 folklore. There were eight such
instructions: AOSE added 1 and then skipped the next instruction
if the result was Equal to zero; AOSG added 1 and then skipped if
the result was Greater than 0; AOSN added 1 and then skipped
if the result was Not 0; AOSA added 1 and then skipped Always;
and so on. Just plain AOS didn't say when to skip, so it never
skipped.
For similar reasons, AOJ meant `Add One and do not Jump'. Even
more bizarre, SKIP meant `do not SKIP'! If you wanted to skip the
next instruction, you had to say `SKIPA'. Likewise, JUMP meant
`do not JUMP'; the unconditional form was JUMPA. However, hackers
never did this. By some quirk of the 10's design, the {JRST}
(Jump and ReSTore flag with no flag specified) was actually faster
and so was invariably used. Such were the perverse mysteries of
assembler programming.
/B-L-T/, /bl*t/ or (rarely) /belt/ n.,vt. Synonym for
{blit}. This is the original form of {blit} and the ancestor
of {bitblt}. It referred to any large bit-field copy or move
operation (one resource-intensive memory-shuffling operation done
on pre-paged versions of ITS, WAITS, and TOPS-10 was sardonically
referred to as `The Big BLT'). The jargon usage has outlasted the
{PDP-10} BLock Transfer instruction from which {BLT} derives;
nowadays, the assembler mnemonic {BLT} almost always means
`Branch if Less Than zero'.
[probably came into prominence with the
appearance of the KL-10 (one model of the {PDP-10}), none of
whose connectors matched anything else] n. The tendency of
manufacturers (or, by extension, programmers or purveyors of
anything) to come up with new products that don't fit together
with the old stuff, thereby making you buy either all new stuff or
expensive interface devices. The KL-10 Massbus connector was
actually *patented* by DEC, which reputedly refused to license
the design and thus effectively locked third parties out of
competition for the lucrative Massbus peripherals market. This is
a source of never-ending frustration for the diehards who maintain
older PDP-10 or VAX systems. Their CPUs work fine, but they are
stuck with dying, obsolescent disk and tape drives with low
capacity and high power requirements.
/D-D-T/ n. 1. Generic term for a program that assists in
debugging other programs by showing individual machine instructions
in a readable symbolic form and letting the user change them. In
this sense the term DDT is now archaic, having been widely
displaced by `debugger' or names of individual programs like
`dbx', `adb', `gdb', or `sdb'.
2. [ITS] Under MIT's fabled {{ITS}} operating system, DDT (running under
the alias HACTRN) was also used as the {shell} or top level command
language used to execute other programs. 3. Any one of several
specific DDTs (sense 1) supported on early DEC hardware. The DEC
PDP-10 Reference Handbook (1969) contained a footnote on the first
page of the documentation for DDT which illuminates the origin of
the term:
Historical footnote: DDT was developed at MIT for the PDP-1
computer in 1961. At that time DDT stood for "DEC Debugging Tape".
Since then, the idea of an on-line debugging program has propagated
throughout the computer industry. DDT programs are now available
for all DEC computers. Since media other than tape are now
frequently used, the more descriptive name "Dynamic Debugging
Technique" has been adopted, retaining the DDT abbreviation.
Confusion between DDT-10 and another well known pesticide,
dichloro-diphenyl-trichloroethane (C14-H9-Cl5) should be minimal
since each attacks a different, and apparently mutually exclusive,
class of bugs.
Sadly, this quotation was removed from later editions of the
handbook after the {suit}s took over and DEC became much more
`businesslike'.
The history above is known to many old-time hackers. But there's
more: Peter Samson, author of the {TMRC} lexicon, reports that
he named `DDT' after a similar tool on the TX-0 computer, the
direct ancestor of the PDP-1 built at MIT's Lincoln Lab in 1957.
The debugger on that ground-breaking machine (the first
transistorized computer) rejoiced in the name FLIT (FLexowriter
Interrogation Tape).
/d*-pib'/ [from the PDP-10 instruction set] vt. To plop
something down in the middle. Usage: silly. "DPB
yourself into that couch there." The connotation would be that
the couch is full except for one slot just big enough for you to
sit in. DPB means `DePosit Byte', and was the name of a PDP-10
instruction that inserts some bits into the middle of some other
bits. This usage has been kept alive by the Common LISP function
of the same name.
n. The heroic age of hackerdom (roughly, pre-1980); the
era of the {PDP-10}, {TECO}, {{ITS}}, and the ARPANET. This
term has been rather consciously adopted from J. R. R. Tolkien's
fantasy epic `The Lord of the Rings'. Compare {Iron Age};
see also {elvish}.
/eks'ch*/ or /eksch/ vt. To exchange two things, each for the
other; to swap places. If you point to two people sitting down and
say "Exch!", you are asking them to trade places. EXCH,
meaning EXCHange, was originally the name of a PDP-10 instruction
that exchanged the contents of a register and a memory location.
Many newer hackers tend to be thinking instead of the {PostScript}
exchange operator (which is usually written in lowercase).
n. 1. The {PDP-10} successor that was to have been built by
the Super Foonly project at the Stanford Artificial Intelligence
Laboratory along with a new operating system. The intention was to
leapfrog from the old DEC timesharing system SAIL was running to a
new generation, bypassing TENEX which at that time was the ARPANET
standard. ARPA funding for both the Super Foonly and the new
operating system was cut in 1974. Most of the design team went to
DEC and contributed greatly to the design of the PDP-10 model KL10.
2. The name of the company formed by Dave Poole, one of the
principal Super Foonly designers, and one of hackerdom's more
colorful personalities. Many people remember the parrot which sat
on Poole's shoulder and was a regular companion.
3. Any of the machines built by Poole's company. The first was the F-1
(a.k.a. Super Foonly), which was the computational engine used to create
the graphics in the movie "TRON". The F-1 was the fastest PDP-10 ever
built, but only one was ever made. The effort drained Foonly of its
financial resources, and they turned towards building smaller, slower,
and much less expensive machines. Unfortunately, these ran not the
popular {TOPS-20} but a TENEX varient called Foonex; this seriously
limited their market. Also, the machines shipped were actually
wire-wrapped engineering prototypes requiring individual attention from
more than usually competent site personnel, and thus had significant
reliability problems. Poole's legendary temper and unwillingness to
suffer fools gladly did not help matters. By the time of the Jupiter
project cancellation in 1983 Foonly's proposal to build another F-1 was
eclipsed by the {Mars}, and the company never quite recovered. See the
{Mars} entry for the continuation and moral of this story.
Origin of the name Foonly
Comment from Joe Smith: In late 1987 I had a chance to see the D. C.
Power Lab (the AI lab was named after Mr. D. C. Power; and not after
an electrical term). One of the guys there was showing off the
space cadet keyboards connected to the KA+KL combo. He mentioned that
DEC had took their design, and the designers, and created the KL-10 as
a scaled-back version of the Foonly. When asked where "Foonly" came
from, the tour guide stated that when someone typed "foo" at the program,
it came back with "foonly". This recollection matches this message
from Edward Rice:
From: ehrice@his.com (Edward Rice)
Newsgroups: alt.folklore.computers,alt.sys.pdp10
Subject: Re: PDP10 clones (was: Compuserve and the DEC-10)
Date: Fri, 06 Oct 1995 14:04:08 -0500
When I asked about this here recently, I received e-mail from
rwa@cs.athabascau.ca (Ross Alexander) with the following explanation:
It comes from the error diagnostic spat out by someone's pdp10
assembler; if you said "foo" to it, it would say "foo: nli"
(not legal instruction). This became a sort of mantra.
As part of a small group that makes jokes about "inpitUL" (pronounced
"in-pi-TUHL" and which stands for "is not presently in the User List"), I
find this entirely plausible.
/hak'mem/ n. MIT AI Memo 239 (February 1972). A
legendary collection of neat mathematical and programming hacks
contributed by many people at MIT and elsewhere. (The title of the
memo really is "HAKMEM", which is a 6-letterism for `hacks
memo'.) Some of them are very useful techniques, powerful
theorems, or interesting unsolved problems, but most fall into the
category of mathematical and computer trivia. Here is a sampling
of the entries (with authors), slightly paraphrased:
Item 41 (Gene Salamin): There are exactly 23,000 prime numbers less
than 2^18.
Item 46 (Rich Schroeppel): The most *probable* suit
distribution in bridge hands is 4-4-3-2, as compared to 4-3-3-3,
which is the most *evenly* distributed. This is because the
world likes to have unequal numbers: a thermodynamic effect saying
things will not be in the state of lowest energy, but in the state
of lowest disordered energy.
Item 81 (Rich Schroeppel): Count the magic squares of order 5
(that is, all the 5-by-5 arrangements of the numbers from 1 to 25
such that all rows, columns, and diagonals add up to the same
number). There are about 320 million, not counting those that
differ only by rotation and reflection.
Item 154 (Bill Gosper): The myth that any given programming
language is machine independent is easily exploded by computing the
sum of powers of 2. If the result loops with period = 1
with sign +, you are on a sign-magnitude machine. If the
result loops with period = 1 at -1, you are on a
twos-complement machine. If the result loops with period greater
than 1, including the beginning, you are on a ones-complement
machine. If the result loops with period greater than 1, not
including the beginning, your machine isn't binary --- the pattern
should tell you the base. If you run out of memory, you are on a
string or bignum system. If arithmetic overflow is a fatal error,
some fascist pig with a read-only mind is trying to enforce machine
independence. But the very ability to trap overflow is machine
dependent. By this strategy, consider the universe, or, more
precisely, algebra: Let X = the sum of many powers of 2 =
...111111. Now add X to itself:
X + X = ...111110 Thus, 2X = X - 1, so
X = -1. Therefore algebra is run on a machine (the
universe) that is two's-complement.
Item 174 (Bill Gosper and Stuart Nelson): 21963283741 is the only
number such that if you represent it on the {PDP-10} as both an
integer and a floating-point number, the bit patterns of the two
representations are identical.
Item 176 (Gosper): The "banana phenomenon" was encountered when
processing a character string by taking the last 3 letters typed
out, searching for a random occurrence of that sequence in the
text, taking the letter following that occurrence, typing it out,
and iterating. This ensures that every 4-letter string output
occurs in the original. The program typed BANANANANANANANA.... We
note an ambiguity in the phrase, "the Nth occurrence of." In one
sense, there are five 00's in 0000000000; in another, there are
nine. The editing program TECO finds five. Thus it finds only the
first ANA in BANANA, and is thus obligated to type N next. By
Murphy's Law, there is but one NAN, thus forcing A, and thus a
loop. An option to find overlapped instances would be useful,
although it would require backing up N - 1 characters before
seeking the next N-character string.
Note: This last item refers to a {Dissociated Press}
implementation. See also {banana problem}.
HAKMEM also contains some rather more complicated mathematical and
technical items, but these examples show some of its fun flavor.
/hi:' mohb'ee/ n. The high half of a 512K {PDP-10}'s
physical address space; the other half was of course the low moby. This
usage has been generalized in a way that has outlasted the
{PDP-10}; for example, at the 1990 Washington D.C. Area Science
Fiction Conclave (Disclave), when a miscommunication resulted in two
separate wakes being held in commemoration of the shutdown of MIT's
last {{ITS}} machines, the one on the upper floor was dubbed the
`high moby' and the other the `low moby'. All parties involved
{grok}ked this instantly. See {moby}.
/I-T-S/ n. 1. Incompatible Time-sharing System, an
influential but highly idiosyncratic operating system written for
PDP-6s and PDP-10s at MIT and long used at the MIT AI Lab. Much
AI-hacker jargon derives from ITS folklore, and to have been `an
ITS hacker' qualifies one instantly as an old-timer of the most
venerable sort. ITS pioneered many important innovations,
including transparent file sharing between machines and
terminal-independent I/O. After about 1982, most actual work was
shifted to newer machines, with the remaining ITS boxes run
essentially as a hobby and service to the hacker community. The
shutdown of the lab's last ITS machine in May 1990 marked the end
of an era and sent old-time hackers into mourning nationwide (see
{high moby}). The Royal Institute of Technology in Sweden is
maintaining one `live' ITS site at its computer museum (right next
to the only TOPS-10 system still on the Internet), so ITS is still
alleged to hold the record for OS in longest continuous use
(however, {{WAITS}} is a credible rival for this palm).
2. A mythical image of operating-system perfection
worshiped by a bizarre, fervent retro-cult of old-time hackers and
ex-users (see {troglodyte}, sense 2). ITS worshipers manage
somehow to continue believing that an OS maintained by
assembly-language hand-hacking that supported only monocase
6-character filenames in one directory per account remains superior
to today's state of commercial art (their venom against UNIX is
particularly intense). See also {holy wars},
{Weenix}.
/jif'kl/, /jaf'kl/, /j*-fi'kl/ vt., obs. (alt.
`jfcl') To cancel or annul something. "Why don't you jfcl that
out?" The fastest do-nothing instruction on older models of the
PDP-10 happened to be JFCL, which stands for "Jump if Flag set and
then CLear the flag"; this does something useful, but is a very
fast no-operation if no flag is specified. Geoff Goodfellow, one
of the jargon-1 co-authors, has long had JFCL on the license plate
of his BMW. Usage: rare except among old-time PDP-10 hackers.
/jerst/ [based on the PDP-10 jump instruction] v.,obs. To
suddenly change subjects, with no intention of returning to the
previous topic. Usage: rather rare except among PDP-10 diehards, and
considered silly. See also {AOS}.
/l*'d*b/ [from the PDP-10 instruction set] vt. To extract
from the middle. "LDB me a slice of cake, please." This usage
has been kept alive by Common LISP's function of the same name.
Considered silly. See also {DPB}.
n. A legendary tragic failure, the archetypal Hacker Dream
Gone Wrong. Mars was the code name for a family of PDP-10
compatible computers built by Systems Concepts (now, The SC Group);
the multi-processor SC-30M, the small uniprocessor SC-25M, and the
never-built superprocessor SC-40M. These machines were marvels of
engineering design; although not much slower than the unique
{Foonly} F-1, they were physically smaller and consumed less
power than the much slower DEC KS10 or Foonly F-2, F-3, or F-4
machines. They were also completely compatible with the DEC KL10,
and ran all KL10 binaries, including the operating system, with no
modifications at about 2--3 times faster than a KL10.
When DEC cancelled the Jupiter project in 1983, Systems Concepts
should have made a bundle selling their machine into shops with a
lot of software investment in PDP-10s, and in fact their spring
1984 announcement generated a great deal of excitement in the
PDP-10 world. TOPS-10 was running on the Mars by the summer of
1984, and TOPS-20 by early fall. Unfortunately, the hackers
running Systems Concepts were much better at designing machines
than in mass producing or selling them; the company allowed itself
to be sidetracked by a bout of perfectionism into continually
improving the design, and lost credibility as delivery dates
continued to slip. They also overpriced the product ridiculously;
they believed they were competing with the KL10 and VAX 8600 and
failed to reckon with the likes of Sun Microsystems and other
hungry startups building workstations with power comparable to the
KL10 at a fraction of the price. By the time SC shipped the first
SC-30M to Stanford in late 1985, most customers had already made
the traumatic decision to abandon the PDP-10, usually for VMS or
UNIX boxes. Most of the Mars computers built ended up being
purchased by CompuServe.
This tale and the related saga of Foonly hold a lesson for hackers:
if you want to play in the Real World, you need to learn Real World
moves.
/moh'bee/ [MIT: seems to have been in use among model
railroad fans years ago. Derived from Melville's `Moby Dick' (some
say from `Moby Pickle').] 1. adj. Large, immense, complex,
impressive. "A Saturn V rocket is a truly moby frob." "Some
MIT undergrads pulled off a moby hack at the Harvard-Yale game."
(See appendix A).
2. n. obs. The maximum address space of a
machine (see below). For a 680[234]0 or VAX or most modern 32-bit
architectures, it is 4,294,967,296 8-bit bytes (4 gigabytes).
3. A
title of address (never of third-person reference), usually used to
show admiration, respect, and/or friendliness to a competent
hacker. "Greetings, moby Dave. How's that address-book thing for
the Mac going?"
4. adj. In backgammon, doubles on the dice, as in
`moby sixes', `moby ones', etc. Compare this with
{bignum} (sense 2): double sixes are both bignums and moby
sixes, but moby ones are not bignums (the use of `moby' to
describe double ones is sarcastic). Standard emphatic forms:
`Moby foo', `moby win', `moby loss'. `Foby moo': a
spoonerism due to Richard Greenblatt.
This term entered hackerdom with the Fabritek 256K memory added to
the MIT AI PDP-6 machine, which was considered unimaginably huge
when it was installed in the 1960s (at a time when a more typical
memory size for a timesharing system was 72 kilobytes). Thus, a
moby is classically 256K 36-bit words, the size of a PDP-6 or
PDP-10 moby. Back when address registers were narrow the term was
more generally useful, because when a computer had virtual memory
mapping, it might actually have more physical memory attached to it
than any one program could access directly. One could then say
"This computer has 6 mobies" meaning that the ratio of physical
memory to address space is 6, without having to say specifically
how much memory there actually is. That in turn implied that the
computer could timeshare six `full-sized' programs without having to
swap programs between memory and disk.
Nowadays the low cost of processor logic means that address spaces
are usually larger than the most physical memory you can cram onto
a machine, so most systems have much *less* than one theoretical
`native' moby of core. Also, more modern memory-management
techniques (esp. paging) make the `moby count' less significant.
However, there is one series of popular chips for which the term
could stand to be revived --- the Intel 8088 and 80286 with their
incredibly {brain-damaged} segmented-memory designs. On these, a
`moby' would be the 1-megabyte address span of a segment/offset
pair (by coincidence, a PDP-10 moby was exactly 1 megabyte of 9-bit
bytes).
[Programmed Data Processor model 10] n. The machine that
made timesharing real. It looms large in hacker folklore because
of its adoption in the mid-1970s by many university computing
facilities and research labs, including the MIT AI Lab, Stanford,
and CMU. Some aspects of the instruction set (most notably the
bit-field instructions) are still considered unsurpassed. The 10
was eventually eclipsed by the VAX machines (descendants of the
PDP-11) when DEC recognized that the 10 and VAX product lines were
competing with each other and decided to concentrate its software
development effort on the more profitable VAX. The machine was
finally dropped from DEC's line in 1983, following the failure of
the Jupiter Project at DEC to build a viable new model. (Some
attempts by other companies to market clones came to nothing; see
{Foonly}) This event spelled the doom of {{ITS}} and the
technical cultures that had spawned the original Jargon File, but
by mid-1991 it had become something of a badge of honorable
old-timerhood among hackers to have cut one's teeth on a PDP-10.
See {{TOPS-10}}, {{ITS}}, {AOS}, {BLT}, {DDT}, {DPB},
{EXCH}, {HAKMEM}, {JFCL}, {LDB}, {pop}, {push}.
n. The most famous computer that never was. {PDP-10}
computers running the {{TOPS-10}} operating system were labeled
`DECsystem-10' as a way of differentiating them from the PDP-11.
Later on, those systems running {TOPS-20} were labeled
`DECSYSTEM-20' (the block capitals being the result of a lawsuit
brought against DEC by Singer, which once made a computer called
`system-10'), but contrary to popular lore there was never a
`PDP-20'; the only difference between a 10 and a 20 was the
operating system and the color of the paint. Most (but not all)
machines sold to run TOPS-10 were painted `Basil Blue', whereas
most TOPS-20 machines were painted `DEC TerraCotta' (not `Chinese Red',
and often mistakenly called orange).
/pip/ [Peripheral Interchange Program] vt.,obs. To copy; from
the program PIP on CP/M, RSX-11, RSTS/E, and OS/8 (derived from a
utility on the PDP-6) that was used for file copying (and in OS/8
and RT-11 for just about every other file operation you might want
to do). It is said that when the program was originated, during the
development of the PDP-6 in 1963, it was called ATLATL (`Anything,
Lord, to Anything, Lord').
/pop'J/ [from a {PDP-10} return-from-subroutine
instruction] n.,v. To return from a digression. By verb doubling,
"Popj, popj" means roughly "Now let's see, where were we?"
See {RTI}.
/P-P-N/, /pip'n/ [from `Project-Programmer Number'] n. A
user-ID under {{TOPS-10}} and its various mutant progeny at SAIL,
BBN, CompuServe, and elsewhere. Old-time hackers from the PDP-10
era sometimes use this to refer to user IDs on other systems as
well.
[from the operation that puts the current information on a
stack, and the fact that procedure return addresses are saved on
a stack] Also PUSH /push/ or PUSHJ /push'J/ (the latter based
on the PDP-10 procedure call instruction). 1. To put something
onto a {stack} or {pdl}. If one says that something has been
pushed onto one's stack, it means that the Damoclean list of things
hanging over ones's head has grown longer and heavier yet. This may
also imply that one will deal with it *before* other pending
items; otherwise one might say that the thing was `added to my queue'.
2. vi. To enter upon a digression, to save the current discussion
for later. Antonym of {pop}; see also {stack}, {pdl}.
n.,obs. /S-O-S/ 1. An infamously {losing} text editor.
Once, back in the 1960s, when a text editor was needed for the
PDP-6, a hacker crufted together a {quick-and-dirty} `stopgap
editor' to be used until a better one was written. Unfortunately,
the old one was never really discarded when new ones (in
particular, {TECO}) came along. SOS is a descendant (`Son of
Stopgap') of that editor, and many PDP-10 users gained the dubious
pleasure of its acquaintance. Since then other programs similar in
style to SOS have been written, notably the early font editor BILOS
/bye'lohs/, the Brother-In-Law Of Stopgap (the alternate expansion
`Bastard Issue, Loins of Stopgap' has been proposed).
2. /sos/
n. To decrease; inverse of {AOS}, from the PDP-10 instruction
set.
/tops-ten/ n. DEC's proprietary OS for the fabled {PDP-10}
machines, long a favorite of hackers but now effectively extinct.
A fountain of hacker folklore. See also {{ITS}},
{{TOPS-20}}, {{TWENEX}}, {VMS}, {operating system}. TOPS-10 was
sometimes called BOTS-10 (from `bottoms-ten') as a comment on the
inappropriateness of describing it as the top of anything.
/tops-twen'tee/ n. See {{TWENEX}}.
/twe'neks/ n. The TOPS-20 operating system by DEC ---
the second proprietary OS for the PDP-10 --- preferred by most
PDP-10 hackers over TOPS-10 (that is, by those who were not
{{ITS}} or {{WAITS}} partisans). TOPS-20 began in 1969 as Bolt,
Beranek & Newman's TENEX operating system using special paging
hardware. By the early 1970s, almost all of the systems on the
ARPANET ran TENEX. DEC purchased the rights to TENEX from BBN and
began work to make it their own. The first in-house code name for
the operating system was VIROS (VIRtual memory Operating System);
when customers started asking questions, the name was changed to
SNARK so DEC could truthfully deny that there was any project
called VIROS. When the name SNARK became known, the name was
briefly reversed to become KRANS; this was quickly abandoned when
it was discovered that `krans' meant `funeral shroud' in
Swedish. Ultimately DEC picked TOPS-20 as the name of the
operating system, and it was as TOPS-20 that it was marketed. The
hacker community, mindful of its origins, quickly dubbed it
{{TWENEX}} (a contraction of `twenty TENEX'), even though by this
point very little of the original TENEX code remained (analogously
to the differences between AT&T V6 UNIX and BSD). DEC people
cringed when they heard "TWENEX", but the term caught on
nevertheless (the written abbreviation `20x' was also used).
TWENEX was successful and very popular; in fact, there was a period
in the early 1980s when it commanded as fervent a culture of
partisans as UNIX or ITS --- but DEC's decision to scrap all the
internal rivals to the VAX architecture and its relatively stodgy
VMS OS killed the DEC-20 and put a sad end to TWENEX's brief day in
the sun. DEC attempted to convince TOPS-20 hackers to convert to
{VMS}, but instead, by the late 1980s, most of the TOPS-20
hackers had migrated to UNIX.
Preface - A little song -
ADVENT - AOS -
BLT - connector conspiracy -
DDT - DPB -
elder days - EXCH -
Foonly - HAKMEM -
high moby - ITS -
JFCL - JRST -
LDB - Mars -
moby - PDP-10 -
PDP-20 - PIP -
POPJ - PPN -
push - SOS -
TOPS-10 - TOPS-20 -
TWENEX
Up to the index for PDP-10 page.
Maintained by Joe Smith at js-cgi@inwap.com