- FXDR David W. Pierce Scripps Instititution of Oceanography What is it FXDR is a library that allows you to make calls to the XDR (eXternal Data Representation) routines from Fortran. You almost certainly already have the XDR routines on your workstation--with FXDR you can easily call them from Fortran. In practical terms, this means that you can read and write unformatted binary files in your ...meteora.ucsd.edu/~pierce/fxdr_home_page.html