Re: Compile on x86, run on ARM?

[Bennett Todd <bet@...>]

2006-02-06T19:47:48 Derek Baker:
> At the moment, we're running on an eval board, and no one seems to know
> if it's little or big. Is there any way to tell using some Linux tool?

I'm almost there, with one little problem. I don't know lua well
enough to do it there, so I'm doing it with perl.

; perl -le 'print((1<<24)+(2<<16)+(3<<8)+4)'
16909060
; perl -e 'print pack("N",16909060)'|od -b
0000000 001 002 003 004
0000004
; perl -e 'print pack("V",16909060)'|od -b
0000000 004 003 002 001
0000004
;

According to the doc in perldoc -f pack:

    N An unsigned long in "network" (big-endian) order.
    V An unsigned long in "VAX" (little-endian) order.

They look opposite to me, but sobeit. If the first octet printed by
od -b is 1, then it's big-endian, and if it's 4 then it's
little-endian (presuming they're all in ascending or descending
order, if they're scrambled then it's middle-endian).

So that's our test number. On PPC:

: minimac; perl -e 'print pack("I",16909060)'|od -b
0000000 001 002 003 004
0000004
: minimac;

On x86:

: pic; perl -e 'print pack("I",16909060)'|od -b
0000000 004 003 002 001
0000004
: pic;

-Bennett

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