Subject: Re: RFC: migration to a fully dynamically linked system
To: Robert Elz <kre@munnari.OZ.AU>
From: Bill Studenmund <email@example.com>
Date: 12/30/2001 11:32:48
On Sun, 30 Dec 2001, Robert Elz wrote:
> In general, I think I'd prefer a static init as well, but ...
> | We could have the kernel try /recovery/init at that point, but how does
> | the kernel know if we're in a, "libc is messed up, try recovery" mode, or
> | a, "we're doomed, panic until someone comes to help" mode?
> That's easy - init can tell the kernel that it is running now, and all is OK.
> After that, panic, before then, try some other init path. init would tell
> the kernel all is OK as just about the first thing it does in main().
> We could invent a new sys call for init to use - wouldn't even need to
> be protected, by the time any other process could possibly get an opportunity
> to issue the sys call, init would have already done it (and this one would
> be a strictly one way operation).
> Or, we could just re-use a sys call that already exists, and that init would
> never normally use - with a "if (curproc->p_pid == 1)" type test added.
> There's even a sys call that does (almost) that test already, so no extra
> overhead would be added if that sys call were adapted for the purpose.
How about just an ioctl on /dev/console?