Copyright | (c) The University of Glasgow 2001 |
---|---|
License | BSD-style (see the file libraries/network/LICENSE) |
Maintainer | libraries@haskell.org |
Stability | provisional |
Portability | portable |
Safe Haskell | Safe-Inferred |
Language | Haskell2010 |
A module containing semi-public Network.Socket internals. Modules which extend the Network.Socket module will need to use this module while ideally most users will be able to make do with the public interface.
Synopsis
- throwSocketError :: String -> IO a
- throwSocketErrorCode :: String -> CInt -> IO a
- throwSocketErrorIfMinus1_ :: (Eq a, Num a) => String -> IO a -> IO ()
- throwSocketErrorIfMinus1Retry :: (Eq a, Num a) => String -> IO a -> IO a
- throwSocketErrorIfMinus1Retry_ :: (Eq a, Num a) => String -> IO a -> IO ()
- throwSocketErrorIfMinus1RetryMayBlock :: (Eq a, Num a) => String -> IO b -> IO a -> IO a
- throwSocketErrorWaitRead :: (Eq a, Num a) => Socket -> String -> IO a -> IO a
- throwSocketErrorWaitReadBut :: (Eq a, Num a) => (CInt -> Bool) -> Socket -> String -> IO a -> IO a
- throwSocketErrorWaitWrite :: (Eq a, Num a) => Socket -> String -> IO a -> IO a
- withSocketsDo :: IO a -> IO a
- zeroMemory :: Ptr a -> CSize -> IO ()
Socket error functions
Throw an IOError
corresponding to the current socket error.
throwSocketErrorCode :: String -> CInt -> IO a Source #
Like throwSocketError
, but the error code is supplied as an argument.
On Windows, do not use errno. Use a system error code instead.
Guards for socket operations that may fail
throwSocketErrorIfMinus1_ Source #
:: (Eq a, Num a) | |
=> String | textual description of the location |
-> IO a | the |
-> IO () |
Throw an IOError
corresponding to the current socket error if
the IO action returns a result of -1
. Discards the result of the
IO action after error handling.
throwSocketErrorIfMinus1Retry Source #
:: (Eq a, Num a) | |
=> String | textual description of the location |
-> IO a | the |
-> IO a |
Throw an IOError
corresponding to the current socket error if
the IO action returns a result of -1
, but retries in case of an
interrupted operation.
throwSocketErrorIfMinus1Retry_ Source #
:: (Eq a, Num a) | |
=> String | textual description of the location |
-> IO a | the |
-> IO () |
Throw an IOError
corresponding to the current socket error if
the IO action returns a result of -1
, but retries in case of an
interrupted operation. Discards the result of the IO action after
error handling.
throwSocketErrorIfMinus1RetryMayBlock Source #
:: (Eq a, Num a) | |
=> String | textual description of the location |
-> IO b | action to execute before retrying if an immediate retry would block |
-> IO a | the |
-> IO a |
Throw an IOError
corresponding to the current socket error if
the IO action returns a result of -1
, but retries in case of an
interrupted operation. Checks for operations that would block and
executes an alternative action before retrying in that case.
Guards that wait and retry if the operation would block
These guards are based on throwSocketErrorIfMinus1RetryMayBlock
.
They wait for socket readiness if the action fails with EWOULDBLOCK
or similar.
throwSocketErrorWaitRead :: (Eq a, Num a) => Socket -> String -> IO a -> IO a Source #
Like throwSocketErrorIfMinus1Retry
, but if the action fails with
EWOULDBLOCK
or similar, wait for the socket to be read-ready,
and try again.
throwSocketErrorWaitReadBut :: (Eq a, Num a) => (CInt -> Bool) -> Socket -> String -> IO a -> IO a Source #
Like throwSocketErrorIfMinus1Retry
, but if the action fails with
EWOULDBLOCK
or similar, wait for the socket to be read-ready,
and try again. If it fails with the error the user was expecting then
ignore the error
throwSocketErrorWaitWrite :: (Eq a, Num a) => Socket -> String -> IO a -> IO a Source #
Like throwSocketErrorIfMinus1Retry
, but if the action fails with
EWOULDBLOCK
or similar, wait for the socket to be write-ready,
and try again.
Initialization
withSocketsDo :: IO a -> IO a Source #
With older versions of the network
library (version 2.6.0.2 or earlier)
on Windows operating systems,
the networking subsystem must be initialised using withSocketsDo
before
any networking operations can be used. eg.
main = withSocketsDo $ do {...}
It is fine to nest calls to withSocketsDo
, and to perform networking operations
after withSocketsDo
has returned.
withSocketsDo
is not necessary for the current network library.
However, for compatibility with older versions on Windows, it is good practice
to always call withSocketsDo
(it's very cheap).