As described in chapter 4, page 311, unit description les (hereafter called PPU les for short), are used to determine if the unit code must be recompiled or not. In other words, the PPU les act as mini-make les, which is used to check dependencies of the di erent code modules, as well as verify if the modules are up to date or not. Furthermore, it contains all public symbols de ned for a module.
The general format of the ppu