PDB (Palm OS)

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	Macintosh time	4 Bytes
0x28	modification time	Macintosh time	4 Bytes
0x2c	backup time	Macintosh time	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]

References