Hi Again, these are archive files. First preserve the media information. If ones wants, one can add other features. Emulators that don't provide some level of I/O interface at a low level usually don't work well for all programs. Emulators should as a minimum, provide a BIOS level interface ( if such exist ). Even this may not be low level enough. If someone writes an emulator that sees things at such a high level as simply files, it will most likely be useless for anything but the simplest programs that could have run on almost any platform. None of the emulators that I've used so far have been at such a high level of I/O. They have all understood drive, track and sector. If you wish to create such an emulator, you can alway post process the archive data ( once ) into whatever format is convenient. There is no particular reason to make archive files emulator friendly. As I've proposed, adding built in language definitions, one could add special purpose functions to do things like extract files based on directory entries. Even if not directly used, existing as source in the archive could provide the emulator writer the methods needed to do such them selves. I'm not saying that we should specifically restrict such from being in the archive file, just that I still don't see why a proper emulator would require such. IMHO Dwight re-creation of media or only be able to re-create media and have a difficult interface in EVERY emulator that needs to access the data? From a usage standpoint, I think putting the burden on the emulators is not a reasonable approach. There are a variety of emulators available do not have to deal with track sector access of information. One uses an import command to bring ms-dos files in for example. To have to write an outside utility that has to know what the image file type is, know the physical layout of the disk, know how the OS accesses files on the disk just to retrieve file data is not a good idea. leave the OS access to the real platform or emulators that want to deal with actual tracks and sectors.