From: Bogdan Costescu (
Date: Mon Mar 09 2009 - 13:16:00 CDT

On Mon, 9 Mar 2009, Axel Kohlmeyer wrote:

> charmm on linux is compiled with gfortran and that uses by default
> 64-bit record seperators in fortran unformatted, and not 32-bit ones
> like everybody else (well, there is a flag to set it, but next to
> nobody uses it).

The gfortran option '-frecord-marker=4' is used by default on x86_64;
in c33 there was a test to check whether it works, but newer versions
of CHARMM don't include this test anymore. c33 is ~3years old and was
the first version to officially support gfortran; since c34, gfortran
is the default compiler used for the 'gnu' architecture (the one used
most often with Linux).

I don't really know where this information that 'next to nobody uses
it' comes from...

Bogdan Costescu
IWR, University of Heidelberg, INF 368, D-69120 Heidelberg, Germany
Phone: +49 6221 54 8240, Fax: +49 6221 54 8850