C++ requires extern "C" linkage specification to call functions from a C library. Enclose the function definitions in subid.h in an extern "C" block if compiling in C++ mode to achieve this. Signed-off-by: Alois Wohlschlager <alois1@gmx-topmail.de>
Signed-off-by: Serge Hallyn <serge@hallyn.com>