linker question

The problem is not the filesystem itself. It works with other files that already are in the system (but not in a library for the moment)

The problem is some instances of File (or a derived version of File). Because the Filesystem::Open() uses a character string (the filename) to look up what the File instance is to use.

So if the tftp server is getting a request for the "testdata.txt", the FileSystem looks for the File instance attached to that name, and returns a pointer to TestDataFile (see examples in my previous post). Here the TestDataFile is never accessed elsewhere in the code directly, and this is exactly what I want to achieve : some parts of the software generate some files with information about the system, without interaction with the main part of the software. It should be stupid if I have to change other parts of the sw if I add a file somewhere.

I can understand your point about the singleton, but I think it will not help me, because in the source file with the problems, I don't need the FileSystem at all. It is the web server (or tftp, ... server) that uses the static FileSystem (Filesystem is a class with all static members, and has no real instance).

Stefaan