Right way to mount/edit dd of a disk?

[Tuc at T-B-O-H.NET]

Hi,

	I have a Linux dd file thats an image of the entire
disk. If I use the fdisk-linux and do :

# fdisk -ul some-big-3.5.0_Update_2-103909.i386.dd
You must set cylinders.
You can do this from the extra functions menu.
Disk some-big-3.5.0_Update_2-103909.i386.dd: 0 MB, 0 bytes
64 heads, 32 sectors/track, 0 cylinders, total 0 sectors
Units = sectors of 1 * 512 = 512 bytes
Disk identifier: 0x00000000
Device Boot      Start         End      Blocks   Id  System
some-big-3.5.0_Update_2-103909.i386.dd1            8192     1535999      763904    5  Extended
some-big-3.5.0_Update_2-103909.i386.dd4   *          32        8191        4080    4  FAT16 <32M
some-big-3.5.0_Update_2-103909.i386.dd5            8224      106495       49136    6  FAT16
some-big-3.5.0_Update_2-103909.i386.dd6          106528      204799       49136    6  FAT16
some-big-3.5.0_Update_2-103909.i386.dd7          204832      430079      112624   fc  Unknown
some-big-3.5.0_Update_2-103909.i386.dd8          430112     1535999      552944    6  FAT16
Partition table entries are not in disk order

	It looks like a good filesystem. So then I :

mdconfig -a -t vnode -f some-big-3.5.0_Update_2-103909.i386.dd -u 0
mount -t msdos /dev/md0s5 /mnt

	to be able to get the dd5 on /mnt. I then edited the files I wanted,
replaced them, and copied back to /mnt. I did "umount /mnt" and copied the dd
file back to where it needed to be.

	It seems it didn't like it, and I'm trying to find out if editing it the
way I did wasn't quite "allowed".

		Thanks, Tuc