File Type $01 (1)
All Auxiliary Types

Full Name: Bad Blocks file
Short Name: Bad blocks

Written by Matt Deatherage (March 1990)

Files of this type and auxiliary type contain blocks that should not be used by the file system.


Files of type $01 contain physical media blocks that should not be used by the file system. A utility program can scan a disk looking for blocks that cannot be read and can then synthesize a file containing those blocks. Such a file should have type $01.

Files of this type should not be touched. If a program finds one, it should leave it alone. If you must delete such a file, be sure to double-check with the user.

Versions of ProDOS 8 prior to 1.8 can cause file system corruption (on ProDOS disks, of course) if you attempt to delete a file of bad blocks, so be sure not to do this. Attempting to delete a bad blocks file is only marginally reasonable for people manually attempting disk repair. A bad blocks scanning utility does not need to delete the old bad blocks files before creating new ones; it should just create new files as necessary. Apple Computer, Inc., does not support deleting a bad blocks file.

The auxiliary types for this file type are reserved; any files created of type $01 should be created with auxiliary type $0000.


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