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From: mike@whuxl.UUCP (BALDWIN)
Newsgroups: net.unix-wizards
Subject: Re: Being `well and truly up the creek'
Message-ID: <820@whuxl.UUCP>
Date: Thu, 14-Nov-85 20:15:28 EST
Article-I.D.: whuxl.820
Posted: Thu Nov 14 20:15:28 1985
Date-Received: Sat, 16-Nov-85 01:31:33 EST
References: <2968@sun.uucp> <2200@umcp-cs.UUCP>
Distribution: net
Organization: AT&T Bell Laboratories, Whippany
Lines: 26

> + /*
> +  * Open the console, and if it fails make a last ditch attempt to
> +  * create a new one.  Assumes fd 0 is not currently open.
> +  */
> + get_console()
> + {
> + 
> + 	if (open(ctty, O_RDWR) == 0)
> + 		return;
> + 	(void) strcpy(ctty, "/#console");
> + 	(void) mknod(ctty, S_IFCHR|0644, 0);
> + 	(void) open(ctty, O_RDWR);
> + 	(void) write(0, "WARNING: /dev/console gone, made /#console\n", 43);
>   }
>   
> In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)

Er, um, what if your console isn't maj,min 0,0?  On my 7300, /dev/console
is 7,0 and the root file system is 0,0 -- writing WARNING over the boot
block would be, like, disastrous.  The only way to *know* what major dev
console is (minor 0 seems OK to assume) is to dig through cdevsw[] -- a
decicedly non-trivial task, and you don't even know that /unix is the
one you booted from anyway.  Oh well.
-- 
						Michael Baldwin
						{at&t}!whuxl!mike