The Unix Heritage Society mailing list
 help / color / mirror / Atom feed
From: "Ron Natalie" <ron@ronnatalie.com>
To: "The Eunuchs Hysterical Society" <tuhs@tuhs.org>
Subject: [TUHS] Re: FD 2
Date: Sun, 29 Jan 2023 19:20:43 +0000	[thread overview]
Message-ID: <emfc4c1646-a458-4e3c-9e39-ca09e9935f74@e41218a5.com> (raw)
In-Reply-To: <CANCZdfqxAZRt-KUEeqqmpg4Q-D39cDQmqjQVSoQoJVYszSUa-A@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 755 bytes --]



>"The main loop of the shell went as follows:
>1) The shell closed all its open files, then opened the terminal 
>special file for standard input and output (file descriptors 0 and 1).
>
Unfortunately, the source code says otherwise.   None of shells V6, PWB, 
V7 do anything like is mentioned above.   They assume 0 and 1 (and 2) 
are already open.
The only fd redirection they do is when you do pipes or redirection on 
the command line.

Where this is done is, as I posted earlier, in /etc/init.    Init opens 
the tty device and dups it to 1 and then invokes either the shell (if 
we're in single user mode) or getty for interactive mode.
This was done in V6 and PWB (1).   In V7, init added a second dup for 
file descriptor 2.

>

[-- Attachment #2: Type: text/html, Size: 2500 bytes --]

  reply	other threads:[~2023-01-29 19:20 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
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 [this message]
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=emfc4c1646-a458-4e3c-9e39-ca09e9935f74@e41218a5.com \
    --to=ron@ronnatalie.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).