Files of this type and auxiliary type contain an archived image of a ProDOS volume.
Davex is a ProDOS 8 command-line shell and program launcher compatible with all Apple II computers that can run ProDOS 8. It supports stuff like wildcards, command history, print spooling, sorted directory listings, and operations on whole directory structures. You can add your own assembly-language commands, too. Davex also allows (coincidentally) saving an image of any ProDOS volume into a file and restoring it later.
For more information on Davex, contact:
DAL Systems
P.O. Box 875
Cupertino, CA 95014
Attention: Davex Technical Support
The first 512 bytes of a Davex archived volume are a header, described under "File Format" in this Note. After the header comes 512 bytes for each block on the saved volume, from zero on up. For blocks that are unused, you can just set the file mark ahead 512 bytes instead of writing 512 zero bytes--this way the unused blocks do not take up disk space, so the resulting file is only a few blocks larger than the number of used blocks on the original volume.
If you run out of room while you are creating an archived volume file, close the file and start another one with the same name on a new disk. The fileNumber field in the header is one in the first file, two in the second file, and so on.
This file format is suitable for ProDOS, but it is less useful on a file system (such as AppleShare) that does not allow for sparse files. A Davex archived volume file on an AppleShare server always takes up more blocks than the original volume contains.
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