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definition:
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connectToSocketRepeat :: Int -> IO _ -> Int -> String -> IO (Maybe Handle)
connectToSocketRepeat waittime action retries nameAtHost = do
let (name,atHost) = break (=='@') nameAtHost
host = if atHost=="" then "localhost" else tail atHost
-- check whether remote CPNS demon is alive:
alive <- cpnsAlive host
if not alive
then tryAgain
else do -- get remote socket/port numbers:
(snr,_) <- getPortInfo name host
if snr==0
then tryAgain
else Socket.connectToSocket host snr >>= return . Just
where
tryAgain = if retries==0 then return Nothing else do
action
sleep (ms2s waittime)
connectToSocketRepeat waittime action (decr retries) nameAtHost
ms2s n = let mn = n `div` 1000 in if mn==0 then 1 else mn
decr n = if n<0 then n else n-1
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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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--- Waits for connection to a Unix socket with a symbolic name.
--- In contrast to `connectToSocket`, this action waits until
--- the socket has been registered with its symbolic name.
--- @param waittime - the time to wait before retrying (in milliseconds)
--- @param action - I/O action to be executed before each wait cycle
--- @param retries - number of retries before giving up (-1 = retry forever)
--- @param nameAtHost - the symbolic name of the socket
--- (must be either of the form "name@host" or "name"
--- where the latter is a shorthand for "name@localhost")
--- @return Nothing (if connection is not possible within the given limits)
--- or (Just h) where h is the handle of the connection
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failfree:
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<FAILING>
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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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connectToSocketRepeat
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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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Prelude.Int -> Prelude.IO a -> Prelude.Int -> String
-> Prelude.IO (Prelude.Maybe System.IO.Handle)
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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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possibly non-reducible on same data term
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