xlc and <sys/dir.h> brain damage

[Bill Wohler]

chuck,

  you haven't fully answered the question.  yes, i know that all the
  compilers are hard linked to xlc using definitions in /etc/xlc.cfg
  and other magic internal variables to produce different behavior
  from the same binary.

  but 1) would one use xlc to compile code using, for example, <sys/dir.h>?
  if so, 2) what magic would one have to perform to get DIR and opendir()
  and so on defined?  i'm not too hip on this standards stuff and
  doing something like defining _POSIX_SOURCE in my makefile gives me
  the heebie-jeebies.  
  
  by the way, is it appropriate for mere mortal programmers to define
  _POSIX_SOURCE, __STDC__, _ANSI_C_SOURCE and so on in ones makefile
  (obviously if they are not set by built-in macros or <standard.h>)?
  perhaps there is a document that describes these standards and
  macros?
-- 
						--bw
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Bill Wohler <wohler at sap-ag.de> <sapwdf!wohler>
Heidelberg Red Barons Ultimate Frisbee Team