External libraries & dlls - How to list all functions signature in shared libraries

Hi All,
I want to know how to list the all the symbols in the shared library(dll or .so file).
I dont want commands like nm or objdump.
I want to get the list of functions available in shared library programmatically at runtime (after calling dlopen and dlsym).
Is there a way to get the complete signature of functions in a shared library??

Please help.

Regards
Nagaraj