  MathLink is Wolfram Research's protocol for communicating with the
Mathematica Kernel and is used extensively in their own Notebook Frontends. The
Mathematica Book insinuates that linking C programs with MathLink is
straightforward but in practice there are quite a number of stumbling blocks,
in particular in cross-language and cross-platform usage. This write-up tries
to clarify the main issues and hopefully makes it easier for software authors
to set up Mathematica interfacing in a portable way.
