When you want to compile source codes, you have to copy your modified source codes ''somewhere'' : usually : a directory. Somewhere
inside or nearby this directory you will put your compilation script or Makefile, and later your objects libraries and
executables.
This bundle of source codes, scripts, object files or libraries and executables is what we call here a ''pack'' :
a ''pack'' is a directory containing specific subdirectories and files, which will be all created running GmkPack .
Below this directory, you will compile your modifications and make your libraries and executables thanks to a script made by GmkPack . All the necessary external files (source codes, libraries) will be accessible inside this pack via symbolic links.
There are two kinds of packs : the ''main'' ones, and the ordinary ones.
A ''main'' pack is what you need to make when you have to compile your whole source code from scratch.
A normal pack is what you need to make when you want to re-compile only a few modifications of a whole source code. In this case you will need to use an existing pack, and your pack will be an increment from this referencing pack. This reference pack may have been made by yourself before the ''ordinary'' one, or or by somebody else.