Subject: Re: Some help with disklabel please?
To: Bill Studenmund <>
From: David Brownlee <>
List: current-users
Date: 08/09/1995 11:18:38
	The definietley sounds like a good idea.

	I guess its mods to the kernel & disklabel
	You could define in the kernel config file what disklabel
	support you wanted.

	options         SUNOS_DISKLABEL

	Maybe a /sys/ufs/disklabels/ directory to hold the code?

	I think its a good idea as well, but I'm also probably not the ideal
	person to do this :(

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On Tue, 8 Aug 1995, Bill Studenmund wrote:

> I'm mailing this follow-up to -current as it touches on a topic I've
> been wondering about, and which (IMHO) should be addressed at a full-
> system level (not just port specific).
> > 
> > > So. . . Two questions:  First, how do I use disklabel under MacBSD;  do I
> > > need to build something like a disktab file first;  or is it just not
> > > functioning yet?  Second, is there a man page that lists the allowed
> > > filesystem types?
> > 
> > 1)  It's not functioning, yet.  I am still thinking about how to handle
> > this.  I'm currently leaning toward continuing an improved version of
> > the current system for disks that will share with MacOS.  On disks that
> > are dedicated to BSD, however, we will handle the standard disklabels.
> [snip]
> I've been wondering about this idea for a while. NetBSD knows how to deal
> with a lot of file systems, including native ones (such as dos and the
> Amiga's OS (I think)). But there is no support for knowing about different
> kinds of disks. So I could compile the dos filesystem code on my mac, but
> I could never hook a dos hard disk up to my Mac as the disktab won't
> find partitions correctly.
> So what would it take to change the drive probing so that all the ports
> could (if so configured) sense the drive type and then disklabel accordingly?
> Basically what I envision is:
> 1) sdXc gets set up to the full disk (all ports leave the full disk in c, no?)
> 2) A series of routines get called to figure out what kind of disk the
>      drive is. The routine looks for its magic cookie and returns true
>      if it matches.
> 3) After a match, a companion routine gets called to build the disktab.
>      Actually, if the port doesn't want the whole disk in c, the port
>      could change it at this step.
> If a drive fails all tests, it gets a BSD disktab. On formats where we
> feel like partitioning, we can write out the disklabes, too. Each port
> would be responsable for writing the sensor and disktab maker for it's
> native OS. But they've already done this, so the only effort is to
> modularize the code and to coordinate things.
> What do people think? Though I'll agree that this feature mightn't get
> used often, I think it might occasionally really-save-someone's-butt in
> a multi-vendor environment.
> I actually wouldn't mind working on this, though I am not really up to
> speed on filesystems, etc, and thus might not be the best person to turn
> loose on it.
> > 
> > -allen
> Take care,
> Bill