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Fortran Calling Sequence

The Run-Time Library now has two entry points (called language bindings) for every routine. One is designed to be called from Fortran only, and the other is designed to be called from C only. The Fortran routines start with ``x'', as in xvread, xladd, etc. They use the same routine names as in the previous RTL.

The Fortran routines are pretty much the same as the old RTL routines. In fact, under VMS, they can be called exactly the same as the old RTL, including being called from C. However, this is only for backwards compatibility - portable routines must never call the Fortran entry points from C, and Fortran routines must use all the new calling conventions. Violating these rules will likely result in a program crash on any machine other than a VAX.