Frustrated trying to be portable

[Doug Gwyn]

In article <4188 at skye.ed.ac.uk> richard at aiai.UUCP (Richard Tobin) writes:
>As far as I can tell, some of the library functions described in the
>standard can be implemented portably (requiring in some cases a
>particular operating system), whereas some others can't.  For example
>the functions from <string.h> and <stdio.h> can, whereas those in
><stdarg.h> can't.

Requiring a particular operating system is hardly a "portable"
implementation.  It is not clear to me that ANY of the standard
library packages specific to a hosted environment can be
implemented perfectly portably.  In any case, the question was
about compilers that apparently were advertised as supporting
"ANSI C".  Hosted vs. freestanding conforming implementations
are the only two sensible categories that chould be so advertised.
An implementation of either category can of course include
additional functionality beyond that specified for the category
in the C standard, subject only to some fairly mild constraints.