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Date: Tue, 04 Aug 2009 23:43:24 +0200
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Spot the error
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On 2009-08-04 22:45, Mel Flynn wrote:
> % mount -t msdofs /dev/label/camera ~/camera
> mount: /dev/label/camera : Operation not supported by device
> 
> I would expect something along the lines of "unknown file system type". Is 
> this fixable?

Yes, just use "msdosfs" instead. ;)  That said, it looks like ENODEV is
returned by vfs_domount(), whenever the fs type is not found in the
list of supported filesystems:

		[...]
		if (fsflags & MNT_ROOTFS)
			vfsp = vfs_byname(fstype);
		else
			vfsp = vfs_byname_kld(fstype, td, &error);
		if (vfsp == NULL)
			return (ENODEV);
		[...]

Note that in the case when vfs_byname_kld() gets called, the error it
returns is silently thrown away. What a pity. :)

In any case, you could paint a lot of bikesheds about which error code
from errno.h would be most suited for this situation, unfortunately.
And there isn't a special "unknown file system" error code, either...