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More benchmarks on heatshrink vs lzexedat
I ran some more meaningful tests comparing the heatshrink and lzexedat depackers. All of these tests are on the amd64 server without KVM. The help and ELD depack tests are with the inline literal store optimisation enabled, apparently speeding up the runs by about 10%, for both heatshrink and lzexedat.
Mid July work, mostly on LZEXE re-use
2025-07-20
This week I got to put LZEXEDAT, the plain LZEXE format compression, to more uses.
LZEXE data compression format
Yesterday I added the LZEXEDAT compression method to inicomp. This currently uses a plain LZEXE format data stream, without any Meta data.
The compression is done by lzexedat.exe, a DOS tool that generates the headerless compressed stream. I added the lzexedat.sh script which deals with leading dotdots then calls dosemu2. (The redirected drive does not allow to use a dotdot to go beyond its root directory, so the script will change the directory of the dosemu2 drive and strip the leading dotdots.)
Early mid July work on lDOS, LZEXE, and MSDebug
2025-07-13, 2025-07-14
This week + Monday some changes were added to the lDOS kernel's comloader (the MZ exe image embedded into the ldos.com file), to the LZEXE ecm fork, and to MSDebug (the ecm fork of MS-DOS's Debug).
The Microsoft EXEPACK compression format: A review
Working on my fork of the 2025 May LZEXE free software release, I also came into contact with Microsoft's EXEPACK. Much has been written about it elsewhere, but a few points remained unclear to me until today as I worked on LZEXE's UPACKEXE. UPACKEXE is an offline depacker for a subset of EXEPACK-packed executables.