unalf is a decompressor for the ALF file format, as used on the Atari 8-bit computers in the late 1980s. Currently, unalf is working and has been fairly well tested against various ALF archives. The ultimate goal of this project is to reimplement the ALF compression and decompression algorithms on modern systems aka Linux and anything else that's POSIX-ish. It's also intended to be a repository of information about the ALF archiver (and UNALF dearchiver). The original LZ.COM/DZ.COM (aka ALF/UNALF) programs for the Atari were written by Alfred. This project is by B. Watson (urchlay@slackware.uk). The rest of this file is a list of the contents of the git repository or distribution tar/zip file. Included in both the source and binary distributions: - README.txt - you're reading it now. - TODO.txt - plans for the future. - doc/Arcinfo - describes the format of ARC compressed files. The ALF file structure is almost identical to ARC's. This file was taken from the arc-5.21q source. - doc/DZ.COM - the Atari executable of the ALF extractor (aka UNALF). This and LZ.COM are the same files as the ones inside the .atr image. - doc/LZ.COM - the Atari executable of the ALF archiver (aka ALF). - doc/alf14.atr - bootable DOS 2.0S disk image, with LZ.COM (aka ALF), DZ.COM (aka UNALF), and the documentation. This is not the original distribution disk: there never was one. Alfred distributed these files as an ARC archive on his BBS. - doc/alf14_doc.txt - the documentation for LZ.COM and DZ.COM, extracted from the disk image and converted from ATASCII to standard ASCII. - doc/fileformat.txt - documents how the ALF file format differs from ARC. - doc/review.txt - a review of the original ALFCrunch, from an Atari magazine. - examples/* - ALF files found in the wild. Included in the source distribution only: - BUILD.txt - directions for compiling unalf. - src/ - the source. - f65/ - "fake 6502" porting layer. Not for the faint of heart. The unalf algorithm was ported from a disassembly of the 6502 code, using a perl script to convert the 6502 mnemonics to C macros. This means I was able to port the code without fully understanding how it works... - testing/alfls - a Perl script that lists the contents of an ALF archive. Run it with --help for more information. If you're packaging unalf for a distribution, there's no need to include this script in the package: I wrote it for testing purposes only. You can use "unalf -l" to list .alf files, so this is redundant. - magic/ - "magic" that allows the file(1) command to identify ALF archive files. See magic/MAGIG.txt for details. Included in the binary distribution only: - README_Windows.txt. - unalf.exe and alfsum.exe - the Windows executables. - unalf.html and alfsum.html - the man pages, converted to HTML.