This is an article from the Svarog386 tech base
Package files provide an easy way to manage software on Svarog386. *** Package filenames *** Packages names must follow some basic rules. They shall be max. 8 letters long (but should not be too short either, since a 1 or 2-letters package name might be confusing), and must not be composed of characters other than a-b, 0-9 and '_'. This for backward compatibility with short file names (8+3) and ISO 9660 file systems (used on CDROMs). The package filename is always followed by the .ZIP extension. *** Package files *** Svarog386 uses ZIP files as its package file format. This format has been chosen because ZIP files under DOS have become the de facto way to distribute collections of files. Also, the ZIP file format is well documented, well supported, and in the public domain. Here below is the RECOMENDED command line that can be used to create a package for a program named EXAMPLE using info-zip: ZIP −9 -r -k EXAMPLE.ZIP subdir1 subdir2 ... subdirN If you are using 7za to create your packages, then use this: 7za a -mm=deflate -mx=9 -tzip EXAMPLE.ZIP subdir1 subdir2 ... subdirN Note, that 7za allows to use different compression algorithms. The Svarog386 package manager (FDNPKG) supports two compression methods: Deflate and LZMA. Usually LZMA provides better compression than Deflate, however it is not recommended for general use because LZMA decompression requires much more memory than Deflate. LZMA decompression needs about 24MiB of memory, which is more than the total available memory on most DOS systems. LZMA might be used for specific packages that assume high-end systems (for example: 3D games, etc). In any case, it's always safer to stick with Deflate. Nevertheless, if you wish to create a package using LZMA, use this: 7za a -mm=lzma -tzip EXAMPLE.ZIP subdir1 subdir2 ... subdirN *** Package directory structure *** A package archive includes both binary and source code. The installer can choose to not unpack sources at install time. The directory structure of a package depends on the type of packages. For "core" packages, we have this: APPINFO Put the program's LSM file here BIN Binaries, such as exe and com files DOC\%PKGNAME% Package documentation HELP The help files NLS\%PKGNAME% Localizations (NLS language files) of the package SOURCE\%PKGNAME% The complete source code Non-core packages use a slightly different directory organization. For example, if we were to consider a package FOO, we might end up with the following structure: APPINFO\FOO.LSM Package meta file for the FOO program PROGS\FOO\FOO.EXE The program's executable PROGS\FOO\FOO.TXT Some documentation PROGS\FOO\FILE.DAT Data file used by the FOO program LINKS\FOO.BAT A "Link" file, see the "links" section for details SOURCE\FOO\* here would be stored all foo's source files Note the 'PROGS' directory above. This is a category to which the package belong. The package installer might change this directory at install time, depending on the user's preferences. Possible categories are listed below: Category | Description DEVEL | Development tools (mostly compilers) DRIVERS | Drivers GAMES | Games PROGS | User programs, tools... Note: "DOC", "NLS", "BIN" and "HELP" directories are strictly reserved to "core" packages. *** Links *** Many utilities are meant to be used from the command line to work on files. Such tools are often expected to be somewhere in the %PATH%, so one do not need to switch to the directory where the said utility is stored to use it. A good example of such tools are archivers (like zip, unrar...), but there are others, too. For such tools, the package format provides a "linking" provision. A package that wishes to put one or more of its executable in the %PATH%, will have to contain a LINKS directory, and in this directory a batch file for every executable that needs to be linked to %PATH%. The batch file must contain ONLY the path and filename to the target executable (as stored in the zip package). During installation, the package manager will substitute these batch files with proper content.