Based on https://github.com/OpenRA/OpenRA/blob/bleed/OpenRA.Game/FileSystem/InstallShieldPackage.cs
isextract is a command line tool to extract from *.z InstallShield v3 packages many old windows games were distributed in.
isextract [mode] [archive] (dir)
mode is either 'l' or 'x', where 'l' lists the contents of the archive and 'x' extracts to the working directory or optionally a directory of your choice.
archive is the path to the archive file.
dir specifies an optional directory that the files should be extracted to.
Bryan Burns for the GPL implementation of a a dos time format convertor. Mark Adler for the open source implementation of the PKWare "explode" algorithm. OpenRA for the C# implementation on which this implementation is based. Veit Kannegieser for STIX on which the OpenRA implementation is based.