I have to add the I've always worked with ASCII strings, so pack and unpack are still magic for me, but I'll keep trying!

No I've tried to unpack the following header: 
Position(bytes)     Datatype
0  - 7              long
8  - 15             long
16 - 23             long
24 - 31             long
32 - 39             long
40 - 43             int
44 - 51             long

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I checked with 'od -l' (on a Unix system):
0000000           0        2000           0         200
0000020           0      455800           0           4
0000040           0           8        2000         275
0000060   281946600   167772160
0000065

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I only know that the 6th value is 2000, which is now the 11th value, so I get the impression that it is expected that a long is only 4 bytes, does that make any sense ?

Now, when I do (on Linux)
my @vals  = unpack("N*", $binrec ) ;
print "@vals" ;

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Output 
0 2000 0 200 0 455800 0 4 0 8 2000 275 281946600

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I get the same values as od except for the last value!
The last thing that confuses me is how to convert a singed/unsiged integer from big to little endian ?

LuCa

In reply to Re: swap binary data from big to little Endian by jeanluca
in thread swap binary data from big to little Endian by jeanluca

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