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definition:
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exclusiveIO :: String -> IO a -> IO a
exclusiveIO lockfile action = do
system $ "lockfile-create --lock-name " ++ lockfile
catch (do actionResult <- action
deleteLockFile
return actionResult )
(\e -> deleteLockFile >> ioError e)
where
deleteLockFile = system $ "lockfile-remove --lock-name " ++ lockfile
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demand:
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no demanded arguments
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deterministic:
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deterministic operation
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documentation:
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--- Forces the exclusive execution of an action via a lock file.
--- For instance, (exclusiveIO "myaction.lock" act) ensures that
--- the action "act" is not executed by two processes on the same
--- system at the same time.
--- @param lockfile - the name of a global lock file
--- @param action - the action to be exclusively executed
--- @return the result of the execution of the action
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failfree:
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(_, _)
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indeterministic:
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referentially transparent operation
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infix:
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no fixity defined
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iotype:
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{(_,_) |-> _}
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name:
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exclusiveIO
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precedence:
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no precedence defined
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result-values:
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_
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signature:
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String -> Prelude.IO a -> Prelude.IO a
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solution-complete:
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operation might suspend on free variables
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terminating:
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possibly non-terminating
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totally-defined:
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reducible on all ground data terms
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