(j3.2006) (SC22WG5.4591) [ukfortran] Comments on N1885

[N.M. Maclaren]

On Nov 18 2011, Malcolm Cohen wrote:
>
> A Fortran procedure cannot do anything async without using async i/o 
> (already covered) or some of the coarray features (also already covered), 
> so in fact you cannot write a procedure in Fortran that is an async 
> communicator.

I agree.  There are only three leaves on the asynchronous communication
procedure tree (those two, plus ones in the coprocessor, as you mentioned
later).  As I read it, Fortran's limited communication with the external
environment (EXECUTE_COMMAND_LINE etc.) is specified to be synchronous.

Van has a fair point in that a vendor could provide conforming extensions
to the language that would enable asynchronicity (e.g. to turn functions
into futures), but I don't see that causes any problems not already
addressed.

Regards,
Nick.