capng_save_state man page
capng_save_state — get the internal library state
capng_save_state is a function that returns a pointer to the internal state of the libcap-ng library. It should be considered opaque and not for alteration directly. This function should be used when you suspect a third party library may use libcap-ng also and want to make sure it doesn't alter something important. This function is not available in the python bindings.
This returns NULL on failure and a non-NULL pointer otherwise.