Suppose you wish to expose a FORTRAN or C function within Matlab without making the effort to write a MEX wrapper. (For instance, writing MEX wrappers for all BLAS/LAPACK routines would be a massive undertaking.) This package will work if:
1) The function is a void type, or the user doesn't care about the function return value.
2) The function arguments are all references to numeric arrays.
Of course, not every function fits the criteria, but it might be easier to write a C wrapper for these tools than to write a MEX wrapper from the ground up. Extend these tools to suit your needs.