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* [TUHS] Dash options
@ 2017-11-29 14:03 Noel Chiappa
  2017-11-29 20:29 ` Charles Anthony
  0 siblings, 1 reply; 22+ messages in thread
From: Noel Chiappa @ 2017-11-29 14:03 UTC (permalink / raw)


    > From: Charles Anthony

    > Entry points are usually defined as "foo$bar", where "foo" is the
    > segment name, and "bar" an entry point in the segment symbol table. I
    > believe that the degerate case of "foo$" is treated as "foo$foo" by the
    > shell.

So I'm curious about how this, and additional names, interact. (For those who
aren't familiar with Multics, a segment [file, sort of] can have multiple
names. This is sort of like 'hard links' in Unix, except that in Multics one
name, the "primary name" is very slightly preeminent. See here:

  http://web.mit.edu/multics-history/source/Multics/mdds/mdd006.compout

page 2-5, for more, if you're interested.)

So if I have a segment with primary name 'foo', and additional names 'bar' and
'zap', and I say 'zap' to the Multics shell, I assume it does a call to
zap$zap, which finds the segment with the primary name 'foo', and calls the
'zap' entry therein?


    > Multics rulez; UNIX droolz

Dude, you clearly have Very Large brass ones to send that to this list! :-)

      Noel


^ permalink raw reply	[flat|nested] 22+ messages in thread
* [TUHS] Dash options
@ 2017-11-29  1:23 Doug McIlroy
  2017-11-29  1:37 ` George Michaelson
  2017-11-29  2:22 ` Charles Anthony
  0 siblings, 2 replies; 22+ messages in thread
From: Doug McIlroy @ 2017-11-29  1:23 UTC (permalink / raw)


Early on, when multics was understood to have
one big, segemented address space, it was expected
that PL/I name qualification ($) would serve to address
segments. I do not know whether that idea was
actually implemented.

Doug


^ permalink raw reply	[flat|nested] 22+ messages in thread
[parent not found: <mailman.376.1511899437.9955.tuhs@minnie.tuhs.org>]
* [TUHS] Dash options
@ 2017-11-28 13:19 Noel Chiappa
  2017-11-28 18:20 ` Clem Cole
  0 siblings, 1 reply; 22+ messages in thread
From: Noel Chiappa @ 2017-11-28 13:19 UTC (permalink / raw)


    > Multics had some kind of `attach' and `detach' of I/O streams, well
    > known to Ossanna, so perhaps dup(2), and a Thompson-shell syntax to go
    > with it meant `>' was earmarked early on.

According to "The Evolution of the Unix Timesharing System", full path names
arrived later than I/O redirection, so by they time they needed a separator,
'>' and '<' were gone. '/' also has the advantage of being a non-shift
character!

	Noel

PS: Re-reading that, I see that early Unix did not have an exec() call (as I
was just discussing); it was done in user mode, with normal read and write
calls.



^ permalink raw reply	[flat|nested] 22+ messages in thread
* [TUHS] Dash options
@ 2017-11-28  5:51 Jon Steinhart
  2017-11-28  6:05 ` Dave Horsfall
  2017-11-28  6:28 ` Greg 'groggy' Lehey
  0 siblings, 2 replies; 22+ messages in thread
From: Jon Steinhart @ 2017-11-28  5:51 UTC (permalink / raw)


Does anybody know the history of dash options?  Were they
a UNIX thing or did UNIX borrow them from something earlier?

Jon


^ permalink raw reply	[flat|nested] 22+ messages in thread

end of thread, other threads:[~2017-12-07  5:15 UTC | newest]

Thread overview: 22+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-11-29 14:03 [TUHS] Dash options Noel Chiappa
2017-11-29 20:29 ` Charles Anthony
  -- strict thread matches above, loose matches on Subject: below --
2017-11-29  1:23 Doug McIlroy
2017-11-29  1:37 ` George Michaelson
2017-11-29  2:22 ` Charles Anthony
     [not found] <mailman.376.1511899437.9955.tuhs@minnie.tuhs.org>
2017-11-28 21:30 ` Paul Ruizendaal
2017-11-28 13:19 Noel Chiappa
2017-11-28 18:20 ` Clem Cole
2017-11-28 21:56   ` Dave Horsfall
2017-11-28  5:51 Jon Steinhart
2017-11-28  6:05 ` Dave Horsfall
2017-11-28  6:49   ` Andrew Warkentin
2017-11-28 11:18     ` Ralph Corderoy
2017-11-28 11:49       ` Michael Kjörling
2017-11-28 12:46         ` Ralph Corderoy
2017-11-28 18:01       ` Lawrence Stewart
2017-11-28 19:36     ` Paul Winalski
2017-11-28 20:03       ` Clem Cole
2017-11-28  6:28 ` Greg 'groggy' Lehey
2017-11-29 19:16   ` Steffen Nurpmeso
     [not found]     ` <20171204054651.GA17671@eureka.lemis.com>
     [not found]       ` <20171204215701.l9Pvr%steffen@sdaoden.eu>
2017-12-05 13:22         ` Steffen Nurpmeso
2017-12-07  5:15           ` Greg 'groggy' Lehey

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