RFC: Time Library 0.1
ashley at semantic.org
Thu Jul 7 04:21:19 EDT 2005
In article <20050706220345.GE26379 at momenergy.repetae.net>,
John Meacham <john at repetae.net> wrote:
> I was thinking for the initial implementation
> getTAITime = do
> lst <- getLeapSecondTable
> t <- getCurrentTime
> return (utcToTAITime lst t)
The problem with this is that it will re-fetch the leap-second table
with every call, at the very least, re-examining the file to see whether
> getLeapSecondTable = do
> -- check for /etc/leapseconds.txt
> -- return contents of file if it exists
> -- else, return built in table.
Returning a built-in table is worse than useless, as any program
compiled with it will soon break.
We could however check for /etc/leapseconds.txt, that might be useful.
But it's not clear what the behaviour on Windows or other platforms
should be. What I'd really like to see is an established cross-platform
convention for providing leap-second tables, and then we could interface
What I am tempted to do is something like this:
readLeapSecondTable :: FilePath -> IO LeapSecondTable
> Of course, getLeapSecondTable and getTAITime will be modified to use any
> local interfaces available or when POSIX eventually specifies some TAI
> interface functions.
What do you mean by "modified to use any local interfaces available"?
Certainly if POSIX does some work here we can provide functions then.
Ashley Yakeley, Seattle WA
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