PGNPack


 * Not to be confused with PGMPAK.

PGNPack is a utility that compresses a PGN file to a special .PPK format. It was developed by Paul W. Onstad.

Discussion
PGN is a format that usually contains a record of one or more chess games.

The purpose of PGNPack is not immediately obvious, but part of it seems to be that the PPK file remains email-compatible (at least for small values of "email-compatible").

PGNPack is a Windows 3.x (GUI) program with a somewhat unusual command-line interface.

The "Version 1.0 (beta)" release may have been the only one.

Identification
PPK files made by PGNPack v1.0-beta start with ASCII "", followed by bytes.

Software

 * PGNPack v1.0-beta:
 * https://pushedpawn.org/downloads/prgs/ → pgnpack.zip
 * https://pushedpawn.org/downloads/prgs/ → pgnpack.zip
 * https://pushedpawn.org/downloads/prgs/ → pgnpack.zip

Sample files

 * → TRIAL.ZIP → TRIAL.PPK