PDB (Palm OS)

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PDB is a container format for record databases in Palm OS, Garnet OS and Access Linux Platform. Its structure is similar to PRC resource databases.[1] The PalmDOC eBook format is a special version of the PDB format.[2]

Structure of PDB file

A PDB file contains a PDB header, PDB record headers and records.[3][4]

PDB Header
PDB Record Header
PDB Records

PDB Header

The PDB header is located at the beginning of the file and contains meta-information on the file:[3]

Offset Name Type Size
0x00 name char 32 Bytes
0x20 file attributes integer 2 Bytes
0x22 version integer 2 Bytes
0x24 creation time MAC OS 9 time - 32bit unsigned integer - number of seconds since midnight, January 1, 1904 GMT 4 Bytes
0x28 modification time MAC OS 9 time - 32bit unsigned integer - number of seconds since midnight, January 1, 1904 GMT 4 Bytes
0x2c backup time MAC OS 9 time - 32bit unsigned integer - number of seconds since midnight, January 1, 1904 GMT 4 Bytes
0x30 modification number integer 4 Bytes
0x34 app_info integer 4 Bytes
0x38 sort_info integer 4 Bytes
0x3c type integer 4 Bytes
0x40 creator integer 4 Bytes
0x44 unique_id_seed integer 4 Bytes
0x48 next_record_list integer 4 Bytes
0x4c num_records integer 2 Bytes

PDB Record Header

For every record, there is an eight byte record header, containing:[3]

name type size notes
offset integer 4 bytes Byte number in the PDB file (counting from zero), where the record is located
attributes byte 1 byte Attributes of the record (delete/dirty/busy/secret/category)
UniqueID integer 3 bytes Always 0

PDB Records

Now the records themselves follow. The usual order is AppInfoArea, SortInfoArea and records, sequentially.[4]

See also

References

  1. N. Rhodes, J. McKeehan. Palm OS Programming, Second Edition, O'Reilly, 2001, ISBN 1-56592-856-3
  2. MobileRead Wiki: Specification of the PalmDOC format
  3. 3.0 3.1 3.2 Paul J. Lucas (1998) PDB (Pilot Database) file format. Accessed on 20090308
  4. 4.0 4.1 Microfirst Software. The Pilot Record Database Format Accessed on 20090308