You say 'little-endian' 32 bit values... so unpack('V30', $doc) is a good place to start, because that's 'little-endian' -- unpack('i30', ...) is a signed 'int', whatever size and byte order that might be.

As noted elsewhere, to get 3759263696 for the first 4 bytes (d0 cf 11 e0) implies these are unsigned 32 bit values. The 'V' pack/unpack form works unsigned. So there's a fit there.

Of course for -1 we now read 0xFFFF_FFFF.

If you really want signed integers, then you can convert all unpacked values >= 0x8000_0000. (This much is obvious.) With Perl v5.10 you can use 'l<' to pack/unpack a 32-bit signed little-endian value.

Update: you can also use 'V!' to pack/unpack a 32-bit signed little-endian value (also Perl v5.10).

(I don't know of a current machine that doesn't use 2's complement, so we need not worry about the form of -ve numbers !)

In reply to Re: To 'pack' or 'unpack' that is the question by gone2015
in thread To 'pack' or 'unpack' that is the question by Wiggins

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