Callback Framework for C++ (source files)
libsigc++_source-2.9.3-1-source
A typesafe callback system for standard C++. It allows you to define signals and to connect those signals to any callback function, either global or a member function, regardless of whether it is static or virtual.
It also contains adaptor classes for connection of dissimilar callbacks and has an ease of use unmatched by other C++ callback libraries.