#define         Platforms:
-------         ----------
ARM_ULIB        Huw Rogers free unix library for acorn archimedes
AZTEC_C         Aztec_C 5.2a
__CYGWIN__      Cygwin
__CYGWIN32__    Cygwin
_DCC            Dice C on AMIGA
__GNUC__        Gnu CC (and DJGPP)
__EMX__         Gnu C port (gcc/emx 0.8e) to OS/2 2.0
__HIGHC__       MetaWare High C
__IBMC__        C-Set++ on OS/2 2.1
_MSC_VER        MS VisualC++ 4.2
MWC             Mark Williams C on COHERENT
__MWERKS__      Metrowerks Compiler; Macintosh and WIN32 (?)
_POSIX_SOURCE   ??
_QC             Microsoft QuickC
__STDC__        ANSI C compliant
__TURBOC__      Turbo C and Borland C
__USE_POSIX     ??
__WATCOMC__     Watcom C on MS-DOS
__ZTC__         Zortech C

_AIX            AIX operating system
__APPLE__       Apple Darwin
AMIGA           SAS/C 5.10 or Dice C on AMIGA
__amigaos__     Gnu CC on AMIGA
atarist         ATARI-ST under Gnu CC
__DragonflyBSD__ DragonflyBSD
__FreeBSD__     FreeBSD
GNUDOS          DJGPP (obsolete in version 1.08)
__GO32__        DJGPP (future?)
hpux            HP-UX
linux           GNU/Linux
macintosh       Macintosh (THINK_C and __MWERKS__ define)
MCH_AMIGA       Aztec_c 5.2a on AMIGA
__MACH__        Apple Darwin
__MINGW32__     MinGW - Minimalist GNU for Windows
MSDOS           Microsoft C 5.10 and 6.00A
_MSDOS          Microsoft CLARM and CLTHUMB compilers.
__MSDOS__       Turbo C, Borland C, and DJGPP
__NetBSD__      NetBSD
nosve           Control Data NOS/VE
__OpenBSD__     OpenBSD
SVR2            System V Revision 2.
sun             SunOS
__SVR4          SunOS
THINK_C         developement environment for the Macintosh
ultrix          VAX with ULTRIX operating system.
unix            most Unix and similar systems and DJGPP (!?)
__unix__        Gnu CC and DJGPP
_UNICOS         Cray operating system
vaxc            VAX C compiler
VAXC            VAX C compiler
vax11c          VAX C compiler
VAX11           VAX C compiler
_Windows        Borland C 3.1 compiling for Windows
_WIN32          MS VisualC++ 4.2 and Cygwin (Win32 API)
_WIN32_WCE      MS Windows CE
vms             (and VMS) VAX-11 C under VMS.

__alpha         DEC Alpha processor
__alpha__       DEC Alpha processor
__hppa__        HP RISC processor
hp9000s800      HP RISC processor
__ia64          GCC on IA64
__ia64__        GCC on IA64
_LONGLONG       GCC on IA64
__i386__        DJGPP
i386            DJGPP
_M_ARM          Microsoft CLARM compiler defines as 4 for ARM.
_M_ARMT         Microsoft CLTHUMB compiler defines as 4 for Thumb.
MULTIMAX        Encore computer
ppc             PowerPC
__ppc__         PowerPC
pyr             Pyramid 9810 processor
__sgi__         Silicon Graphics Inc.
sparc           SPARC processor
sequent         Sequent computer
tahoe           CCI Tahoe processor
vax             VAX processor
__x86_64        AMD Opteron