What namespaces are available?

[Tim McDaniel]

karl at haddock.ima.isc.com (Karl Heuer) writes (marked with ">"):
>	_[a-z0-9][_A-Za-z0-9]*	what I called semi-reserved

karish at forel.stanford.edu (Chuck Karish) writes (marked with "%"):
% These names are reserved for possible use by the implementation,
% according to Section 4.1.2 of the May, 1988 draft of the dpANS.  If
% they are used in application programs, the behavior is undefined.
% They are, however, usable by programmers.
%
% If you're writing NON-PORTABLE library functions to support
% applications in a specific hardware/software environment, you can use
% this namespace (after checking for actual conflicts on your particular
% system) without polluting the namespace that is available for portable
% programs.
%
% Chuck Karish	karish at denali.stanford.edu
% 		hplabs!hpda!mindcrf!karish
% 		(415) 493-7277

This behavior just seems so useless.  It's not a problem for me,
understand; it's just something I'm scratching my head over and saying
"What were they thinking of?".

If I use the semi-reserved namespace, I have to "check for actual
conflicts on my particular system" (with the implementation and with
other libraries) and can avoid "polluting the namespace that is
available for portable programs."  I have to check the implementation
uses because it might be using semi-reserved names.

If I use the reserved namespace, I HAVE TO DO THE EXACT SAME THINGS.
Either way, it's non-portable.  Either way, the user namespace is not
polluted.

Am I missing something obvious?  If so, PLEASE let me know and I'll
just shut up.

--

             Tim, the Bizarre and Oddly-Dressed Enchanter

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