Specifies a single directory where hard drive image difference files are stored. Hard drive image difference files store any data that is written back to a hard disk image, in order to preserve the original image. Not all the drivers supporting hard disk images enable this feature but, if they do, the differencing files are created at startup.

The default is diff (that is, a directory diff in the same directory as the MESS executable).

If this directory does not exist, it will be automatically created.

mess -diff_directory <path>