by Lorenz Huelsbergen. Describes the implementation of a general interface to C for SML/NJ, including the ability to expose ML closures as C function pointers.
SWIG generate interfaces from (extended) ANSI C/C++ function and variable declarations. It can generate output for Tcl/Tk, Python, Perl5, Perl4 and Guile-iii. More information available via the SWIG home page.
FFIGEN is a tool that parses C header files and presents an intermediate data representation suitable for writing backends. More information available via the FFIGEN home page.
Header2Scheme is a program which reads C++ header files and compiles them into C++ code. This code implements the back end for a Scheme interface to the classes defined by these header files. See . the Header2Scheme home page for more information.