CVS, in its "Entries" file stores the timestamp that the file was last changed, so that you can check if it has been updated.
The timestamp is formatted like this: "Mon Dec 7 14:59:26 2010"
Now, to a human that's a perfectly readable format. But if you want a computer to understand it you've got to separate it into its component parts which are _completely_ out of order.
ISO 8601 is the international standard. And following that, the format would be "2010-12-20T14:59:26Z". Which is slightly harder to read as a human (because it's all smooshed together), but so much easier to parse with a computer. And has the bonus that if you sort a bunch of dates using normal character order they'll come out correctly.
CVS gets a bit of an out for being created in 1986, 2 years before ISO 8601. But as ISO 3307 was available from 1975, there were standards they totally _could_ have used.
(I can't find details on what the ISO 3307 date-time format looked like, but ISO 2014 said to use YYYY-MM-DD, so I can only assume that ISO 3307 did something reasonably sensible.)
Next task for today: Write a parser for that date format.
(And look forward to a glorious future when I won't have to touch CVS any more.)
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