Thanks for comments from several folk, fix from Doug Bates and start to finding new email for ucminf maintainer. Summary of responses: DBLEPR and its relations are briefly mentioned but with no or minimal examples in Writing R Extensions as well as Venables and Ripley book. I should have emphasized I was especially seeking examples, and Brian Ripley has pointed out that cluster, mda and tweedie among others use these routines. Fortran WRITE or PRINT routines, even if unused by code, may interfere with C output, especially in Windows. (See R-devel post from Brian Ripley). Doug Bates provided a different approach and code that appears to fix ucminf. We have a lead on contacting the maintainer, who has moved, so hopefully the package can be updated. My conclusion from this: xxxPR routines are still usable, but likely not the best approach for output from Fortran routines. Once again, thanks to all. JN