1 Volume Header
ksherlock edited this page 2015-04-23 11:48:11 -04:00

This is the volume directory, as originally defined in ProDOS/SOS.

Name Offset Size
storage_type $00 4 bits (high)
name_length $00 4 bits (low)
file_name $01 15 bytes
reserved $10 8 bytes
creation $18 4 bytes
version $1c 1 byte
min_version $1d 1 byte
access $1e 1 byte
entry_length $1f 1 byte
entries_per_block $20 1 byte
file_count $21 2 byte
bit_map_pointer $23 2 bytes
total_blocks $25 2 bytes

Updates

  • Part of the reserved data is used to store the modification date. This is not documented but is reportedly specific to the GS/OS ProDOS FST.
  • Part of the reserved data is used to store file_name case information as of IIgs System 5. Refer to GS/OS Technote #8.
Name Offset Size
storage_type $00 4 bits (high)
name_length $00 4 bits (low)
file_name $01 15 bytes
reserved $10 2 bytes
last_mod $12 4 bytes
file_name_case_bits $16 2 bytes
creation $18 4 bytes
version $1c 1 byte
min_version $1d 1 byte
access $1e 1 byte
entry_length $1f 1 byte
entries_per_block $20 1 byte
file_count $21 2 byte
bit_map_pointer $23 2 bytes
total_blocks $25 2 bytes