To do so, you have to mount the Hard disk/ISO image in a folder, read/write the .image and .changes files and then unmount.
Mounting the virtual hard drive
In case you are using the VM appliance, you'll mount the VM disk's file system inside your real file system. You can do that with this command (which gets installed with VMWare Player)
$ vmware-mount SqueakNOS.vmdk /vmdiskYou have read/write access here, so you can work with normal squeak, save the image and finally copy it overwriting SqueakNOS.* inside the mounted directory. When you are done you do
$ vmware-mount -k ../SqueakNOS.vmdkto unmount. When you restart the VM you'll see all the changes you did from the outside.
Accessing the ISO image
Here we get into trouble: ISO images can only be mounted as read-only. This means that you'll be able to read the files inside it, but wouldn't be able to write to it a new image in case you make a change from the outside. To solve this problem, you can regenerate the ISO with a new image.
Unpack the .iso in some place, overwrite the .squeakNOS.image/changes files and then issue:
~/isocontent/ $ cd platforms/SqueakNOS ~/isocontent/platforms/SqueakNOS$ make isothat will generate in
releasefolder a new bootable .iso with the image you just placed.