EPACK (executable compression)
EPACK is an executable compression utility for DOS, developed by Oleg V. Stepanyuk.
Whether EPACK is its official name is not completely certain, but there's nothing better to refer to it by.
Format details
An EPACKed file is really a special self-extracting compressed file format. When executed, it writes the original file to a temporary file, executes it, then deletes it.
The envelope format is always DOS EXE, and the temporary filename is always "TEMP.EXE". The payload file could be in any format compatible with this mechanism. In practice, that means certain EXE formats, and COM.
Identification
[Only v1.6 has been evaluated.] The first 3920 bytes of a compressed file are always the same, though there is little in the way of plain-text signatures. The string "TEMP.EXE" appears at offset 883.
Software
- EPACK, at old-dos.ru
- ANORMAL's DOSEXE collections → DOSEXE Executable Tools Pack → packers/epack.160-Stepanyuk Oleg.rar
