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@@ -79,7 +79,11 @@ module GHC.IO.Handle |
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withFileDescriptorReadingBiased,
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withFileDescriptorWritingBiased,
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withWindowsHandleReadingBiased,
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- withWindowsHandleWritingBiased
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+ withWindowsHandleWritingBiased,
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+ withFileDescriptorReadingBiasedRaw,
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+ withFileDescriptorWritingBiasedRaw,
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+ withWindowsHandleReadingBiasedRaw,
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+ withWindowsHandleWritingBiasedRaw
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-- ** Caveats
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-- $with-ref-caveats
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@@ -90,7 +94,7 @@ import GHC.Internal.IO.Handle |
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import GHC.Internal.Control.Monad (return)
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import GHC.Internal.Control.Concurrent.MVar (MVar)
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import GHC.Internal.Control.Exception (mask)
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-import GHC.Internal.Data.Function ((.), ($))
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+import GHC.Internal.Data.Function (const, (.), ($))
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import GHC.Internal.Data.Functor (fmap)
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#if defined(mingw32_HOST_OS)
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import GHC.Internal.Data.Bool (otherwise)
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@@ -132,11 +136,11 @@ import GHC.Internal.Foreign.C.Types (CInt) |
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{-|
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Obtains an operating-system handle that underlies a Haskell handle and
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- executes a user-provided action on it. The Haskell-managed buffers related
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- to the operating-system handle are flushed before the user-provided action
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- is run. While this action is executed, further operations on the Haskell
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- handle are blocked to a degree that interference with this action is
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- prevented.
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+ executes a user-provided action on it. Before the user-provided action is
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+ run, user-defined perparation based on the handle state that contains the
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+ operating-system handle is performed. While the user-provided action is
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+ executed, further operations on the Haskell handle are blocked to a degree
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+ that interference with this action is prevented.
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See [below](#with-ref-caveats) for caveats regarding this operation.
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-}
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@@ -149,16 +153,18 @@ withOSHandle :: String |
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-}
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-> (forall d. Typeable d => d -> IO a)
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-- ^ Conversion of a device into an operating-system handle
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+ -> (Handle__ -> IO ())
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+ -- ^ The preparation
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-> Handle
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-- ^ The Haskell handle to use
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-> (a -> IO r)
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-- ^ The action to execute on the operating-system handle
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-> IO r
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-withOSHandle opName handleStateVar getOSHandle handle act
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+withOSHandle opName handleStateVar getOSHandle prepare handle act
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= mask $ \ withOriginalMaskingState ->
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withHandleState $ \ handleState@Handle__ {haDevice = dev} -> do
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osHandle <- getOSHandle dev
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- flushBuffer handleState
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+ prepare handleState
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withOriginalMaskingState $ act osHandle
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where
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@@ -272,6 +278,7 @@ withFileDescriptorReadingBiased :: Handle -> (CInt -> IO r) -> IO r |
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withFileDescriptorReadingBiased = withOSHandle "withFileDescriptorReadingBiased"
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handleStateVarReadingBiased
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getFileDescriptor
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+ flushBuffer
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{-|
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Obtains the POSIX file descriptor that underlies a handle or specifically
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@@ -290,6 +297,7 @@ withFileDescriptorWritingBiased :: Handle -> (CInt -> IO r) -> IO r |
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withFileDescriptorWritingBiased = withOSHandle "withFileDescriptorWritingBiased"
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handleStateVarWritingBiased
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getFileDescriptor
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+ flushBuffer
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{-|
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Obtains the Windows handle that underlies a Haskell handle or specifically
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@@ -308,6 +316,7 @@ withWindowsHandleReadingBiased :: Handle -> (Ptr () -> IO r) -> IO r |
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withWindowsHandleReadingBiased = withOSHandle "withWindowsHandleReadingBiased"
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handleStateVarReadingBiased
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getWindowsHandle
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+ flushBuffer
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{-|
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Obtains the Windows handle that underlies a Haskell handle or specifically
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@@ -326,17 +335,62 @@ withWindowsHandleWritingBiased :: Handle -> (Ptr () -> IO r) -> IO r |
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withWindowsHandleWritingBiased = withOSHandle "withWindowsHandleWritingBiased"
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handleStateVarWritingBiased
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getWindowsHandle
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+ flushBuffer
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+
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+{-|
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+ Like 'withFileDescriptorReadingBiased' except that Haskell-managed buffers
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+ are not flushed.
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+-}
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+withFileDescriptorReadingBiasedRaw :: Handle -> (CInt -> IO r) -> IO r
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+withFileDescriptorReadingBiasedRaw
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+ = withOSHandle "withFileDescriptorReadingBiasedRaw"
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+ handleStateVarReadingBiased
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+ getFileDescriptor
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+ (const $ return ())
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+
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+{-|
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+ Like 'withFileDescriptorWritingBiased' except that Haskell-managed buffers
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+ are not flushed.
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+-}
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+withFileDescriptorWritingBiasedRaw :: Handle -> (CInt -> IO r) -> IO r
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+withFileDescriptorWritingBiasedRaw
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+ = withOSHandle "withFileDescriptorWritingBiasedRaw"
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+ handleStateVarWritingBiased
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+ getFileDescriptor
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+ (const $ return ())
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+
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+{-|
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+ Like 'withWindowsHandleReadingBiased' except that Haskell-managed buffers
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+ are not flushed.
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+-}
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+withWindowsHandleReadingBiasedRaw :: Handle -> (Ptr () -> IO r) -> IO r
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+withWindowsHandleReadingBiasedRaw
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+ = withOSHandle "withWindowsHandleReadingBiasedRaw"
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+ handleStateVarReadingBiased
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+ getWindowsHandle
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+ (const $ return ())
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+
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+{-|
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+ Like 'withWindowsHandleWritingBiased' except that Haskell-managed buffers
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+ are not flushed.
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+-}
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+withWindowsHandleWritingBiasedRaw :: Handle -> (Ptr () -> IO r) -> IO r
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+withWindowsHandleWritingBiasedRaw
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+ = withOSHandle "withWindowsHandleWritingBiasedRaw"
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+ handleStateVarWritingBiased
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+ getWindowsHandle
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+ (const $ return ())
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-- ** Caveats
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{-$with-ref-caveats
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- #with-ref-caveats#There are the following caveats regarding each of the
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- above operations:
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+ #with-ref-caveats#There are the following caveats regarding the above
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+ operations:
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- * The flushing of buffers can fail if the given handle is readable but not
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+ * Flushing of buffers can fail if the given handle is readable but not
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seekable.
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- * If the operation is performed as part of an action executed by
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+ * If one of these operation is performed as part of an action executed by
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'unsafePerformIO', 'unsafeInterleaveIO', or one of their “dupable”
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variants and the user-provided action receives an asychnchronous
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exception and does not catch it, then the following happens:
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