How can I detect undefined symbols in a binary/library?

Question

Is there a tool that takes a binary (executable) or a library and, looking also into any shared library dependencies, finds and lists any undefined symbols (even if they are not used)? Any practical way of finding this?

Answer 1

If using *nix, and symbols have not been stripped, using 'nm' will help.

# nm lib-or-binary-name
U strcmp@@GLIBC_2.2.5

The 'U' means undefined, and if it is satisfied somewhere, that will be noted after the @.