Re: gfortran "partial" recursive I/O support

[Jerry DeLisle <jvdelisle at verizon dot net>]

Tobias Burnus wrote:
> FX wrote:
> > >  So, until we have implemented derived type I/O we can only claim 
> > > partial
> > > recursive I/O.
> > >     
> > I don't think that's it: Cray, g95 and Intel all have no support for
> > derived-types I/O and yet have a "yes" for recursive I/O.
> >   
>
> The table follows ftp://ftp.nag.co.uk/sc22wg5/N1601-N1650/N1648.pdf, 
> which has:
>
> "4.10 Recursive input/output -- A recursive input/output statement is 
> one that is executed while another input/output statement is in 
> execution. We met this in connection with derived-type input/output 
> (Section 4.1). The only other situation in which it is allowed, and this 
> is an extension from Fortran 95, is for input/output to/from an internal 
> file where the statement does not modify any internal file other than 
> its own."
>
> Our conclusion was: "Yes, but" and playing cautious we put a "partially" 
> there. Maybe we can come to a new conclusion.  See for the initial 
> discussion:

I have spent some time searching the internet.  I conclude that gfortran fully 
supports recursive I/O to/from internal units and contrary to the standard, also 
allows this to/from external files.

I also have to say, so far, I have not found one shred of code that uses this 
feature.  I am not saying there is not someone somewhere doing so.  I think a 
diagnostic for the external case is way down on the list of priorities.

Jerry