2 Extended File
ksherlock edited this page 2015-04-23 11:54:29 -04:00
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Introduction

Extended files are used for storing files which contain a resource fork. They are not supported by ProDOS 8.

storage_type $05

The key_pointer is a block containing 2 mini entries; one for the data fork (at offset $0), one for the resource fork (at offset $100).

Mini Entry

Name Offset Size
storage_type $00 1 byte
key_block $01 2 bytes
blocks_used $03 2 bytes
eof $05 2 bytes

Unlike the File Entry storage_type field, the high nibble is 0. The only valid values are $01, $02, or $03.

As of System 6.0, Macintosh finder information can be stored after the data fork mini entry (starting offset of $08).

Name Offset Size Value
size_1 $00 1 byte 18
type_1 $01 1 byte 1
FInfo $02 16 bytes ...
size_2 $12 1 byte 18
type_2 $13 1 byte 2
xFInfo $14 16 bytes ...
end_mark $24 1 byte 0

One or both of FInfo and xFInfo may be missing, in which case they should be considered 0-filled.

References