Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!zaphod.mps.ohio-state.edu!wuarchive!uunet!beartrk!ceilidh!dnichols
From: dnichols@ceilidh.beartrack.com (DoN Nichols)
Newsgroups: comp.sys.3b1
Subject: Re: swap space
Message-ID: <1991Jun15.192831.23511@ceilidh.beartrack.com>
Date: 15 Jun 91 19:28:31 GMT
References: <1991Jun9.170520.4087@yenta.alb.nm.us> <1991Jun11.030216.6155@ceilidh.beartrack.com> <100425.7286@timbuk.cray.com>
Organization: D and D Data, Vienna, VA.
Lines: 48

In article <100425.7286@timbuk.cray.com> andyw@aspen32.cray.com (Andy Warner) writes:
>
	[ ... my mistaken assumption deleted ... ]
>
>This probably won't work. I'll defer to anyone with access to the
>source, but the kernel doesn't use /dev/swap, that's just for things like
>ps. Most V.2 kernels use three variables rootdev, swapdev & pipedev to
>find their root, swap & pipe device. These are either compiled into the
>binary (though they are variables, so you can patch them with adb), or
>are picked up from the Volume Header Block of the boot disk. I don't
>know if the Convergent VHB hold information about what a slice is to
>be used for (I've got a feeling it doesn't). One good thing is that
>I'm sure they pick up the size of the swap device from the VHB, so you
>don't have to tweak that.

	Looking at the /usr/include/sys/gdisk.h file to check for this, I
found something that looks interesting.  Does this mean that I can have a
filesystem automatically mount itself (aside from under the control of
/etc/rc)?  If so, when would this happen?  Does it happen only for
removable-media drives like the Syquest?  How about a floppy?  I can see why
I might want to have removable-media drives automount, but is there any
reason for doing things this way with a normal disk partition?  Is there any
good reason for this to exist?  Why am I asking all these questions ... ?

/*      volume home block on disk       */
struct vhbd {
        uint    magic;          /* S4 disk format code */
        int     chksum;         /* adjustment so that the 32 bit sum starting

	[ ... ]

        char    fpulled;        /* dismounted last time? */
***>>>  struct  mntnam mntname[MAXSLICE];       /* names for auto mounting.
                                                        null string means no
                                                        auto mount */
        long    time;           /* time last came on line */

	[ ... ]
};


	Thanks
		DoN.
-- 
Donald Nichols (DoN.)		| Voice (Days):	(703) 664-1585
D&D Data			| Voice (Eves):	(703) 938-4564
Disclaimer: from here - None	| Email:     <dnichols@ceilidh.beartrack.com>
	--- Black Holes are where God is dividing by zero ---