Darklands catalog files

Files with this format: "*.cat"; "bc"; "lcastle"; "msgfiles".

Catalog files are basically a filesystem; each one contains a large set of (usually related) files.

Table of Contents

Offsets

Structures

Offsets

Offset: starting at 0x00

0x00: num_entries: word

Number of file entries.

0x02: entries: array[ num_entries ] of struct entry (each size 0x18)

File entries.

Offset: starting at entry[0].offset

[next]: contents: array[ num_entries ] of unknown (entry[idx].length bytes)

Contents of the files.

• For a given index, the contents start at entry[idx].offset, and are entry[idx].length long.

Structures

Structure: entry

Size 0x18.

0x00: filename: string(12)

Name of the file.

• Always in 8.3 format.
• Padded with nulls if the filename is shorter.

0x0c: timestamp: dword

Timestamp of when the file was added to the archive.

• This might be something else, but all the values in a single cat file are very close together. a00c.cat has a timestamp about a minute before e00c.cat, and this field is about 0x40 (64) higher in e00c.cat. That would imply it's a number of seconds since an epoch. Additionally, einfo.cat (timestamped half a year earlier) has numbers much smaller.
• Epoch seems to be around 3/1/1979, although I could be mistaken. 1/1/1980 would make more sense.

0x10: length: dword

Length of the contents.

0x14: offset: dword

Offset to the contents.