From: ron minnich <rminnich@gmail.com>
To: Warner Losh <imp@bsdimp.com>
Cc: The Eunuchs Hysterical Society <tuhs@tuhs.org>
Subject: [TUHS] Re: FD 2
Date: Sun, 22 Jan 2023 17:10:15 -0500 [thread overview]
Message-ID: <CAP6exY+e7+YBsFG3PuoNV6Wm6RkxW=8pX5czKudki1Vy0EEDcw@mail.gmail.com> (raw)
In-Reply-To: <CANCZdfrnO-a7bUGRVHtGLdkGFYeaNCyTzwdR1tO+keKkmKf9cA@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 1903 bytes --]
Thanks very much for this interesting archaeological dig.
On Sun, Jan 22, 2023, 4:23 PM Warner Losh <imp@bsdimp.com> wrote:
>
>
> On Sat, Jan 21, 2023 at 11:37 AM Warner Losh <imp@bsdimp.com> wrote:
>
>>
>> Yea. Like many things, there was a transition... the most important bit
>> is the shell. And that was more tricky to read through with the phone at
>> breakfast...
>>
>
> OK. I've dug a bit further and Clem and I have chatted... Here's the
> summary.
>
> We don't have V4's shell, alas, since all we have from that time period is
> the C kernel a few months before the 4th edition release. V5 /bin/sh closes
> fd2 and then dups fd1 to fd2. This creates fd2 as something special. V6
> closes all FD's larger than 1 (2-15) and then does the dup(1) which it
> makes sure returns 2 or it closes the file. While there were features in V6
> to allow use of fd2/stderr, few programs used then.
>
> And neither crypt nor passwd reads from fd2. crypt reads from fd0, while
> passwd doesn't read. It just replaces the hashed password with the new
> password. I've also looked at pr because
>
> >I do remember that pr -p actually read from FD 2. It probably still does.
>
> and that's not true in V7 at least... pr didn't have a 'p' arg :). Maybe
> later programs started to do these things, but most of what went on with V7
> was a transition to most error messages on stderr, which typically went to
> stdout in V6.
>
> So, people remembering it coming in with V7 are right, in the sense it was
> the first release to do it consistently. And the people remembering V4 or
> V5 are also right, in a different sense because the shell was ensuring fd2
> was a copy of fd1 there, which a couple of programs (diff) used for errors.
> And I believe that the impetus for the V7 changes was phototypesetting
> 'file not found' too often... But that last bit is mostly because I want
> to believe.
>
> Warner
>
[-- Attachment #2: Type: text/html, Size: 2777 bytes --]
next prev parent reply other threads:[~2023-01-22 22:11 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-20 22:44 [TUHS] " ron minnich
2023-01-20 22:54 ` [TUHS] " G. Branden Robinson
2023-01-20 22:56 ` Rob Pike
2023-01-20 23:11 ` Larry McVoy
2023-01-20 23:14 ` Rob Pike
2023-01-20 23:22 ` Larry McVoy
2023-01-20 23:13 ` Douglas McIlroy
2023-01-21 3:37 ` Jon Steinhart
2023-01-21 15:42 ` Clem Cole
2023-01-21 17:34 ` Warner Losh
2023-01-21 17:50 ` Warner Losh
2023-01-21 18:26 ` Clem Cole
2023-01-21 18:37 ` Warner Losh
2023-01-22 11:05 ` Jonathan Gray
2023-01-22 21:23 ` Warner Losh
2023-01-22 22:10 ` ron minnich [this message]
2023-01-23 7:30 ` arnold
2023-01-23 8:32 ` James Johnston
2023-01-23 8:58 ` G. Branden Robinson
2023-01-23 11:49 ` Brantley Coile
2023-01-23 14:25 ` Ronald Natalie
2023-01-23 17:43 ` Brantley Coile
2023-01-23 16:59 ` Douglas McIlroy
2023-01-24 7:21 ` arnold
2023-01-29 18:51 ` Warner Losh
2023-01-29 19:20 ` Ron Natalie
2023-01-29 20:25 ` Warner Losh
2023-01-30 7:50 ` arnold
2023-01-30 8:09 ` Rob Pike
2023-01-30 15:02 ` Larry McVoy
2023-01-30 15:16 ` Dan Cross
2023-01-30 15:27 ` Larry McVoy
2023-01-30 15:35 ` Dan Cross
2023-01-30 15:45 ` Larry McVoy
2023-01-30 16:09 ` Dan Cross
2023-01-30 16:18 ` Larry McVoy
2023-01-30 19:03 ` Dan Cross
2023-01-30 19:12 ` Brantley Coile
2023-01-30 21:24 ` Larry McVoy
2023-01-30 22:15 ` Rob Pike
2023-01-30 22:50 ` ron minnich
2023-01-30 23:05 ` [TUHS] Child of plan9? (Re: " Bakul Shah
2023-01-31 3:19 ` [TUHS] " Andrew Warkentin
2023-01-30 16:21 ` [TUHS] " Steve Nickolas
2023-01-30 16:27 ` Larry McVoy
2023-01-30 16:32 ` ron minnich
2023-01-30 16:40 ` Clem Cole
2023-01-30 19:55 ` Lawrence Stewart
2023-01-31 21:27 ` Dave Horsfall
2023-01-30 16:48 ` Theodore Ts'o
2023-01-30 16:57 ` Andy Kosela
2023-01-30 17:04 ` Warner Losh
2023-01-30 20:38 ` Theodore Ts'o
2023-01-30 21:01 ` Warner Losh
2023-01-30 21:10 ` Clem Cole
2023-01-30 16:03 ` Bakul Shah
2023-01-30 16:07 ` Larry McVoy
2023-01-30 16:13 ` Bakul Shah
2023-01-30 16:22 ` Steve Nickolas
2023-01-30 16:17 ` Dan Cross
2023-01-30 16:18 ` Ralph Corderoy
2023-01-30 16:41 ` [TUHS] job control (Re: " Bakul Shah
2023-01-30 19:07 ` [TUHS] " Dan Cross
2023-01-30 13:26 ` John Cowan
2023-01-30 14:30 ` arnold
2023-01-30 0:25 ` Phil Budne
2023-01-30 2:08 ` Warner Losh
2023-01-21 18:27 ` Clem Cole
2023-01-22 10:56 ` Jaap Akkerhuis via TUHS
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAP6exY+e7+YBsFG3PuoNV6Wm6RkxW=8pX5czKudki1Vy0EEDcw@mail.gmail.com' \
--to=rminnich@gmail.com \
--cc=imp@bsdimp.com \
--cc=tuhs@tuhs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).