Re^7: Why is pack("N",42949672965) giving me 00 00 00 05

pack takes a bunch of bits and interprets them in whatever way you tell if to

That's what unpack does, as you demonstrated. pack, on the other hand, is very specific about what it takes.

Passing negative numbers where an unsigned one is expected currently performs a C cast, but it's undocumented behaviour.

Neither I nor Perl can see any difference

To see the difference between using 0xFFFF_FFFF and -1, you just had to substitute 0xFFFF_FFFF for -1 instead of writing an entirely new program. Try again.

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Re^8: Why is pack("N",42949672965) giving me 00 00 00 05 by BrowserUk (Patriarch) on Feb 10, 2015 at 04:23 UTC
Still no difference!: `print pack('N', -1) eq pack('N', 0xffff_ffff) ? 'Same' : 'Different';; Same print pack('N', -1) eq pack('N', 0xFFFF_FFFF) ? 'Same' : 'Different';; Same` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". I'm with torvalds on this In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked With the rise and rise of	[reply] [d/l]
Re^9: Why is pack("N",42949672965) giving me 00 00 00 05 by soonix (Chancellor) on Feb 10, 2015 at 07:42 UTC
ikegami most probably wants to point out the fact that, with a 'Q' specifier, `0xFFFF_FFFF` will give a different result. While you are certainly right that for "all F's" it is easier to write "one short of overflow", hence "-1", he is certainly right in pointing out that simply going from `0xFFFF_FFFF` to `0xFFFF_FFFF_FFFF_FFFF` may be an incorrect oversimplification.	[reply] [d/l] [select]
Re^10: Why is pack("N",42949672965) giving me 00 00 00 05 by BrowserUk (Patriarch) on Feb 10, 2015 at 07:54 UTC
ikegami most probably wants to point out the fact that, with a 'Q' specifier, 0xFFFF_FFFF will give a different result. Hm. But that isn't what he said! What he said was: "your very question demonstrates that -1 and 0xFFFF_FFFF pack differently.". Which is patently and demonstrably wrong. And I don't see any mention of using OxFFFF_FFFF in conjunction with the Q specifier in Tux post. Indeed Tux didn't use, nor advocate the use of 0xFFFF_FFFF at all. The whole point of his post was: "Why not simply use -1?" which he demonstrated did the right thing with both 'N' & 'Q'. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". I'm with torvalds on this In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked	[reply]