A Tale of Two File Names: deconstructing the checksum in Windows 8.3 file names

Re:A Tale of Two File Names: deconstructing the checksum in ... by jstanley on Wednesday June 10, 2015 @06:03AM (#9690939)

Really interesting article, sounds like a fun adventure. Couple of points:

1.) "0x12b9b0a5. This equals 314159269 in decimal. Yep, that’s the first 8 digits of pi right there" -- actually, it's not. The first 8 digits of pi are 3.14159265, it's not clear why the Microsoft developers ended with a 9 instead of a 5, perhaps a mistake? perhaps to help with coprime-ness?

2.) The "ANSI C" version uses mbstowcs which isn't any kind of ANSI C function I've ever heard of.

Fantastic article, really enjoyed reading, many thanks.

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Re:A Tale of Two File Names: deconstructing the checksum in ... by Quackmatic on Wednesday June 10, 2015 @06:12AM (#9690966)

> The first 8 digits of pi are 3.14159265

Those are the first 9 digits if you count 3 - the 9 at the end is the 9th digit, not the 8th, so the first 8 digits are correct. You're correct about the ANSI C part though, it's actually C99 - I've corrected that part. Thanks.

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Re:A Tale of Two File Names: deconstructing the checksum in ... by jstanley on Wednesday June 10, 2015 @06:15AM (#9690983)

pi begins: 3.141592653589 - I miscounted 8 instead of 9, but the number is still wrong.

EDIT: Oh, I see what you mean. He's saying the first 8 digits of that are the first 8 digits of pi, although the 9th is incorrect. Got it.

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Re:A Tale of Two File Names: deconstructing the checksum in ... by to3m on Wednesday June 10, 2015 @11:28AM (#9692908)

It claims to be "standard C", which usually these days means ISO C rather than ANSI C. For details about mbstowcs, see the C99 standard, section 7.20.8.1.

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