>I am running netbsd on a PC and want to partition my hard disk to have
>a small MS-DOS partition (bitten by the DOOM bug I'm afraid ;-).  I
>have succeeded in partitioning the disk so that both NetBSD and DOS
>happily coincide.  The partitioning I have looks like this:
>
>a:      0 -   31 cyls   DOS
>b:      32 - 201 cyls   NetBSD
>c:      32 - 201 cyls   NetBSD "whole disk"

One question (not related to anything else):  Are these Unix partition letters?
If so, then I assume it's not your boot disk.

>Now when I try to mount the DOS partition I get an error about invalid
>arguments (definitely not "device not configured").  Now, I _do_ have
>the MSDOSFS option configured into the kernel as I can mount a DOS
>floppy.  I suspect that my partitioning is not right but the above
>solution was the only one I could find that did not screw up the DOS
>partition when I did a disklabel under NetBSD.  Help!

EINVAL (the "invalid arguments") error means that it didn't see a MS-DOS
partition in that space.  What isn't so obvious is that generally a MS-DOS
partition doesn't start at exactly cylinder 0 - room is left for the partition
info and MBR.  So actually the DOS partition generally starts later on the
disk.  You can use the NetBSD fdisk program to find out the exact geometry of
the DOS partition, and plug that into disklabel.

Good luck!

--Ken