lkml.org 
[lkml]   [2000]   [Feb]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: /dev/console should it always be available?
Date
In article <cistron.20000226114501.D9382@alice.realminfo.com>,
Mike Panetta <mpanetta@realminfo.com> wrote:
>Should /dev/console always be available even if there is no
>video card or keyboard on a machine?

You could simply link it to /dev/null

>I keep getting these
>messages in the logs about init not being able to open(/dev/console)
>when I remove the video card from an embedded box I am working on.
>when I do this strange things start to happen like it cannot properly
>umount /dev/hda5 (not root partition) on shutdown, and mingetty starts
>to respawn to fast.

Those are userlevel programs that cannot cope with not having a
console. That's not a kernel issue I think.

>This is related to a previous message I sent to the
>list about a week ago reguarding the ext2 corruption messages without
>a video card in the machine. Since then I have upgraded all the libraries
>to be compilant with the rquirements in Documentation/Changes and the
>corruption has gone away.

Ah, but did you upgrade the e2fstool as well? Those might have
caused the corruption in the first case.

Often a program doesn't check if stdin, stdout and stderr are
really opened at the start of the program, it is simply assumed
they are open and they are fd# 0, 1 and 2.

Now if that program is fsck, and it opens /dev/hda1 to check it,
and it happens to get filedescriptor #1 back from open(), image
what happens if the program does a printf("checking /dev/hda1 .. \n");

At least mount(1) had a bug like this (the garbage ended up in
/etc/mtab), other tools might as well.

So it's probably a good idea to link /dev/console to /dev/null.

Mike.
--
"dhbgr zr ba guvf bar - biretnna bc Rkpunatr vf rra jvwf orfyhvg" -- ZnepbU.
(punatrq gb ebg13 nsgre frireny frevbhfyl fbhaqvat guerngf).

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:56    [W:0.189 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site