Question

Is there a manual or a method available to find out which file libXX.so contains the functions and so on from the header YYY.h ?

For example:

I include a header foo.h with the function foofunk() inside.
But the linker says undefined reference to foofunk().

Note:

I want to use a Makefile for the build and link process. (GCC)
And my sources are in C, but that should be unimportant.

Answer 1

Use objdump.

objdump -T library.so | grep ' Base ' | grep ' function_name$'

Now loop over shared libraries you suspect of defining a given function and check each of them using objdump.

for f in /usr/lib/lib*.so; do \
  objdump -T $f | grep ' Base ' | grep -q ' function_name$' && echo $f && break
done

Remove break if you want to continue searching despite having found the library you’re looking for.

In case of static libraries substitute -T with -t and get rid of one of greps.

objdump -t library.a | grep ' function_name$'