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Ciaran McCreesh posted on Wed, 25 Nov 2009 21:27:18 +0000 as excerpted: |
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> Portage uses two ways of merging a file: os.rename() and the manual way. |
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> |
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> os.rename() correctly preserves mtimes. |
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> |
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> Python's os.utime call, which is what Portage uses to preserve mtimes |
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> for files that it installs the hard way, and which is not a wrapper for |
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> the Unix utime call, uses an IEEE 754 double to handle timestamps. But a |
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> double only gives sixteen accurate decimal digits, and you've got ten to |
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> the left of the decimal point, leaving only six reliably preserved, with |
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> the remaining three digits being corrupted. |
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> |
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> Thus, packages can end up being installed with some files having |
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> accurately-preserved mtimes, and some having corrupted mtimes, which |
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> will lead to mtime comparisons giving incorrect results. |
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That's a great explanation (thanks, I now know the details to the degree |
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I'd be interested), but what was asked for was examples of breakage, aka |
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actual bugs. I seem to remember either you or someone else mentioning |
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that there had been a couple issues already, and I'll take the claim at |
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face value, but actual bug numbers would be nice. =:^) |
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"Every nonfree program has a lord, a master -- |
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and if you use the program, he is your master." Richard Stallman |
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