[TUHS] The ^ = | ?

[TUHS] The ^ = | ?

[Norman Wilson]

The earliest UNIX Programmer's Manual to describe shell
pipelines is the Third Edition, February 1973.  It gives a
syntax quite different from the modern one:

	com1 > com2 > com3 > outfile

meant what we would now write as

	com1 | com2 | com3 > outfile

This original syntax was pretty cumbersome; pretty
obviously it was put in as a quick hack (as were many
things in those early days).  Because > and < applied
only to the following word, pipelined commands with
arguments had to be quoted:

	who > "grep ken" >/tmp/kenlogins

Even worse, the shell had no inherent way to tell whether
the final word was a file or a program; if the last element
in a pipeline was to write to standard output, you had to
say so explicitly:

	who > "grep ken" >

On the other hand the syntax was symmetric: you could
also write

	"grep ken" < who <

pipe(II) also debuted in the Third Edition.

By the Fourth Edition (November 1973) there had evidently
been more time to think about the syntax; the modern notation
is shown, except that ^ is allowed as a synonym for |.  I have
long guessed that was because in those dark days of the
past, some upper-case-only terminals (remember stty lcase?)
offered no way to type | (and perhaps likewise {}`~) but I don't
really know.  Dennis?

Norman Wilson
Toronto ON

[TUHS] The ^ = | ?

[Warren Toomey]

In article by Norman Wilson:
> The earliest UNIX Programmer's Manual to describe shell
> pipelines is the Third Edition.

I don't have Peter Salus' book `A Quarter Century of UNIX'
here at home, but I think this topic is discussed in the
book. Dennis Ritchie's paper:

http://cm.bell-labs.com/cm/cs/who/dmr/hist.html

talks about the change from > to `another symbol', but not explicitly
the ^.

[TUHS] The ^ = | ?

[Lars Brinkhoff]

Warren Toomey <wkt at minnie.tuhs.org> writes:
> From my memory of Salus' book, the > syntax was relaced by ^, but
> when Ken went to the U.K to give a talk, he made the decision to
> switch over to the | symbol.
> 
> Anyway, I could be completely wrong about this being in Salus'
> book, so if I am, I'll have to hunt down where this info came from.

You are right.  Pages 51-53 (in the 1995 reprint).

-- 
Lars Brinkhoff          http://lars.nocrew.org/     Linux, GCC, PDP-10,
Brinkhoff Consulting    http://www.brinkhoff.se/    HTTP programming

[TUHS] The ^ = | ?

[Sven Mascheck]

Norman Wilson wrote:

> The earliest UNIX Programmer's Manual to describe shell
> pipelines is the Third Edition, February 1973.

BTW: As the manual source isn't trivial to process on many new systems,
i had converted sh(1) from V3, V4, V6, PWB and V7 into html:
<http://www.uni-ulm.de/~s_smasch/various/bourne/#predecessors>

Sven

[TUHS] The ^ = | ?

[Greg Lehey]

On Thursday, 23 January 2003 at 22:09:51 -0500, Norman Wilson wrote:
>
> By the Fourth Edition (November 1973) there had evidently been more
> time to think about the syntax; the modern notation is shown, except
> that ^ is allowed as a synonym for |.  I have long guessed that was
> because in those dark days of the past, some upper-case-only
> terminals (remember stty lcase?)  offered no way to type | (and
> perhaps likewise {}`~) but I don't really know.

Certainly the [AK]SR-33 didn't have {}~.  I had this funny feeling
that they did have |, but it doesn't make sense, and I'm probably
wrong.

A thing to recall is that the shape of some of the symbols was
somewhat different in those days.  In particular, _ was a backarrow
(pointing left), and ^ was an uparrow, making it look much more like |
than it appears nowadays.

Greg
--
Finger grog at lemis.com for PGP public key
See complete headers for address and phone numbers

[TUHS] The ^ = | ?

[Wolfgang Helbig]

>I've been searching for some reference to the ^ symbol being the same a | in
>Bourne shell. Does anyone remember seeing anything like this? I've searched
>the early manpages to no avail.

Look at
	http://www.ba-stuttgart.de/~helbig/os/v6/doc/index.html
for the Unix V6 sh(I) man page. 

Greetings,

Wolfgang

[TUHS] The ^ = | ?

[Carl Lowenstein]

> From: "Lange, David" <Extern.David.Lange at gedas.com>
> To: "'tuhs at minnie.tuhs.org'" <tuhs at minnie.tuhs.org>
> Subject: [TUHS] The ^ = | ?
> 
> Greetings,
> 
> I've been searching for some reference to the ^ symbol being the same a | in
> Bourne shell. Does anyone remember seeing anything like this? I've searched
> the early manpages to no avail.

It's here in my printed copy of the 6th Edition Unix Programmer's Manual.

Page entitled SH(I)
Section DESCRIPTION
Subsection Command lines.  One or more commands separated by '|' or '^'
constitute a chain of filters.  . . .

    carl

-- 
    carl lowenstein         marine physical lab     u.c. san diego
                                                 clowenst at ucsd.edu

[TUHS] The ^ = | ?

[M. Warner Losh]

In message: <47F5ADC94EF3C14AA51386CD1A20DDB8036D5EB6 at usvwoaahs51>
            "Lange, David" <Extern.David.Lange at gedas.com> writes:
: I've been searching for some reference to the ^ symbol being the same a | in
: Bourne shell. Does anyone remember seeing anything like this? I've searched
: the early manpages to no avail.

OS-MP 4.3D (SunOS 4.1.3) man pages say:

     A pipeline is a sequence of one or more  commands  separated
     by  `|'  (or,  for  historical  compatibility, by `^').  The

Warner

[TUHS] The ^ = | ?

[John Holden]

> I've been searching for some reference to the ^ symbol being the same a |

Yes, pre Bourne shell, edition 6 and earlier used ^ for piped. Also chdir
insteads of the shortened 'cd'

[TUHS] The ^ = | ?

[Lange, David]

Greetings,

I've been searching for some reference to the ^ symbol being the same a | in
Bourne shell. Does anyone remember seeing anything like this? I've searched
the early manpages to no avail.

Regards,

	D.