[Distutils] Package DB: strawman PEP

[Thomas Heller]

From: "Robin Becker" <robin@jessikat.fsnet.co.uk>
> well there is stuff in the registry related to installations and shared
> dlls have some kind of user count there too. There's also a registry
> folder containing information about uninstall info.
> 
> In my Win2K for example I can't find python21.dll in the shared modules
> list. Somewhere there must be an explanation of how and what is supposed
> to be done by an installer.

All this is only a convention on windows, there is no package
manager enforcing these things.
- The registry contains reference counts of shared dlls,
the installers and uninstallers have to maintain them
and observe them.
- The registry contains some entries which will show up
in the add/remove programs control panel applet, and
a command line which will start the deinstaller.

The deinstaller itself has to be provided by the installer,
and the installer always has to feed the deinstaller with information
about files to delete, registry entries to remove, and so on.
The WISE installer, for example, has this information in the INSTALL.LOG
file, Installshield has something like uninst.isu, and so on.
bdist_wininst installers write 'Remove<package>.exe' as the uninstaller,
and '<package>-wininst.log' has the list of files and directories
installed.

(All this may be different with the new windows installer service, but
I don't know much about that)

Thomas