Thanks to Olin and Brent for your comments.
It appear, that I've found a principal problem with dlopen() on
SVR4. I don't have a linker option, which was suggested by Brent, to
make all symbols available to dlsym(). On SVR4 dlsym() seems to only
find symbols, which reside in shared objects.
I think, this is the same problem, which causes problems with perl
5.000, when you want to use the dynamic loading option.
What I'm going to try is, that I put all *.o into a shared library and
link main.o with this shared library. This should give me access to
all symbols through dlsym().
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