Re: emergency or init=/bin/sh mode and terminal signals

From: linux-os (Dick Johnson)
Date: Mon Jun 19 2006 - 07:35:56 EST



On Sun, 18 Jun 2006, Samuel Thibault wrote:

> Hi,
>
> There's a long-standing issue in init=/bin/sh mode: pressing control-C
> doesn't send a SIGINT to programs running on the console. The incurred
> typical pitfall is if one runs ping without a -c option... no way to
> stop it!
>
> This is because no session is set up by the kernel, and shells don't
> start sessions on their own, so that no session (hence no controlling
> tty) is set up.
>
> The attached patch sets such session and controlling tty up, which fixes
> the issue. The unfortunate effect is that init might be killed if one
> presses control-C very fast after its start.
>
> Samuel
>

I don't think this is the correct behavior. You can't allow some
terminal input to affect init. It has been the de facto standard
in Unix, that the only time one should have a controlling terminal
is after somebody logs in and owns something to control. If you want
a controlling terminal from your emergency shell, please exec /bin/login.

Cheers,
Dick Johnson
Penguin : Linux version 2.6.16.4 on an i686 machine (5592.88 BogoMips).
New book: http://www.AbominableFirebug.com/
_


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