Endianness of freeBSD
Heiko Wundram (Beenic)
wundram at beenic.net
Mon Feb 4 12:18:52 UTC 2008
Am Montag, 4. Februar 2008 13:03:25 schrieb navneet Upadhyay:
> 1. Is FreeBSD little Endian like windows?
FreeBSD endianness depends on the hardware architecture it runs on (as
endianness is a hardware characterization). (Very) generally, anything that's
related to an Intel CPU is little-endian, whereas anything that's related to
a Motorola, IBM or Sparc CPU is big-endian.
(Modern) Windows exists only on little-endian hardware [Intel, AMD and clones]
(AFAIK, someone correct me here), so basically it's always little-endian, you
could say that. There were Windows versions for other CPUs, though, back in
the Windows NT days, which ran on Alpha workstations which were big-endian.
> 2. Linux is Big endian?
Same as for FreeBSD.
> wrote a code int i = 1; if((i >> 1) == 0) little else big
> got little on all platforms bsd,linux,windows.
This won't tell you what endianness the platform has. It'll say "little" for
any architecture (because ( 1 >> 1 ) == 0 for any CPU that knows how to do
What you can use to test for little or big-endianness, is something like the
unsigned long test = 0x12345678;
char* ptest = (char*)&test;
if( *ptest == 0x78 )
else if( *ptest == 0x12 )
<something else ?>
> *Does endianness depends on OS or the hardware?*
As I said above: it depends on the hardware. There is even hardware (ARM, in
particular) which can run in little- or big-endian mode, depending on how it
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