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Date: 21 Oct 2009 14:42:33 +0100
From: "N.M. Maclaren" <nmm1@cam.ac.uk>
To: SC22WG5 <sc22wg5@open-std.org>
Subject: Re: [ukfortran] (SC22WG5.4097) (j3.2006) Standard intrinsics andcoarrays
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On Oct 21 2009, Bill Long wrote:
>Malcolm Cohen wrote:
>> Bill Long wrote:
>>> If an environment variable is never changed during execution of the 
>>> program, then I don't see an issue with GET_ENVIRONMENT_VARIABLE 
>>> either.
>> 
>> Why would we expect the same environment variables to exist for the 
>> whole program?
>
>I would expect that the program launching mechanism would establish the 
>same environment for each image.  However, as Nick's second version 
>proposal suggests, this might not be true for some cases.

It's definitely not true, and can't be!

Consider variables like SSH_TTY for something where propagating them is
precisely the wrong thing to do.  Or propagating some of the TERMxxx
variables to systems that don't recognise them :-(

>The "processor-dependent" approach is better.  A user who wants portable 
>code would call GET_ENVIRONMENT_VARIABLE only on image 1. It might be 
>worth adding that suggestion to Nick's NOTE.

A good point.  Also for the other 'command environment' ones and
DATE_AND_TIME - zones :-(

I forgot COMMAND_ARGUMENT_COUNT, too, which is one of those.

Regards,
Nick.