Peter Tanski wrote:
Now each GHC-Haskell-based program installer would search /usr/local/lib for, say, libHSrts_dyn-6.6.1.dylib and install that version if necessary. What happens on uninstall? The same thing you get on Windows when you have another program using a particular .DLL--the uninstall of that version of the library would fail but for unix systems _only_ if you also have another program using at while you are doing the uninstall. So if you did not break everything on each install, eventually you have a complete mess of different versions of GHC libraries in /usr/local/lib that may have no current use but at one time were used for several GHC-Haskell-based programs that have now been upgraded to use something different. Hopefully those who distributed the binary programs adopted a convention of using the full version of the library instead of symlinking libHSrts_dyn-6.6.1 to libHSrts_dyn, or as a user several of your older programs might break after a later one installed a new version of the library and symlinked that the new version...
That is why I think your idea was good: put everything into distinct directories.
We are not intending to build-in any particular knowledge about where shared libraries are to be installed - that's up to the packager. With one exception - we have to pick a default for the .tar.bz2 binary distributions (and 'make install'), and the only default that makes sense is to install the shared libraries in the standard location, /usr/local/lib. Otherwise the system will not find them, and GHC itself will not run (assuming it is dynamically linked). You don't get good uninstall support, but that's always been the way if you don't use the system package manager. Cheers, Simon