Subject: re: MFS over ISO-9660 union mounted with no swap space?
To: Erik E. Fair <>
From: Frederick Bruckman <>
List: tech-kern
Date: 05/12/1999 04:01:46
On Tue, 11 May 1999, Erik E. Fair wrote:

> At 17:20 -0700 5/11/99, matthew green wrote:
> >here is my MFS fstab line for my /tmp:
> >
> >	swap	/tmp	mfs	rw
> Um, mine looks the same way, however, you're missing the point. That mount
> is a standard mount, where everything underneath the mount point (if there
> were anything) would be inaccessible. I was talking about a "union" mount
> of MFS on top of a CD-ROM FS where everything on the CD-ROM would still be
> accessible. How would you express that? I think I might need new options
> for mount_mfs...

You use the common "mount -o" options like this:

	swap   /tmp     mfs     rw,union

which is analogous to this:

	mount -t mfs -o union swap /tmp

If you want to specify "mount_mfs" specific options, like size, do it
like this:

	swap   /m       mfs     rw,union,-s=2880

The -o options are described in mount(8). I don't know where else the
fstab usage is documented but in the example fstabs in /usr/src/etc/etc.*.
Looking at the the fstab manpage, I just noticed another omission--`xx',
for commenting out fs's doesn't work, but shell style `#' comments do.