[fpc-pascal] FORTRAN from FreePascal

[brian]

I need to try to put a user-friendly GUI and some graphical output
onto an old command-line FORTRAN number cruncher, and have been
provided with around 130 KB of FORTRAN source code. A quick scan of
documentation seems to suggest that this is possible using gfortran
and the C calling conventions (if someone knows differently, please
say so right now!) :)

My knowledge of FORTRAN-77 is sound, if rather rusty, but I know
almost nothing about C programming, having been brought up as a
chemist before I was dragged across to programming (I learned to
program on Algol-60, BASIC and FORTRAN-IV, yes, that long ago ): ).

Anyone with any past experience here? It seems I have two choices, to
try to call the FORTRAN subroutines from FreePascal or to port the
FORTRAN code to Pascal, I'm looking for advice...

Thanks,

Brian.