GI.Gio.Interfaces.PollableOutputStream

PollableOutputStream is implemented by GOutputStreams that can be polled for readiness to write. This can be used when interfacing with a non-GIO API that expects UNIX-file-descriptor-style asynchronous I/O rather than GIO-style.

Exported types

newtype PollableOutputStream

Constructors

PollableOutputStream (ManagedPtr PollableOutputStream)

Instances

GObject PollableOutputStream

Methods

gobjectType :: PollableOutputStream -> IO GType

IsObject PollableOutputStream

IsOutputStream PollableOutputStream

IsPollableOutputStream PollableOutputStream

((~) * info (ResolvePollableOutputStreamMethod t PollableOutputStream), MethodInfo * info PollableOutputStream p) => IsLabel t (PollableOutputStream -> p)

Methods

fromLabel :: Proxy# Symbol t -> PollableOutputStream -> p

((~) * info (ResolvePollableOutputStreamMethod t PollableOutputStream), MethodInfo * info PollableOutputStream p) => IsLabelProxy t (PollableOutputStream -> p)

Methods

fromLabelProxy :: Proxy Symbol t -> PollableOutputStream -> p

HasAttributeList * PollableOutputStream

type AttributeList PollableOutputStream

type AttributeList PollableOutputStream

type SignalList PollableOutputStream

type SignalList PollableOutputStream

noPollableOutputStream :: Maybe PollableOutputStream

class GObject o => IsPollableOutputStream o

Instances

(GObject a, UnknownAncestorError Constraint PollableOutputStream a) => IsPollableOutputStream a

IsPollableOutputStream PollableOutputStream

IsPollableOutputStream MemoryOutputStream

IsPollableOutputStream UnixOutputStream

IsPollableOutputStream ConverterOutputStream

toPollableOutputStream :: IsPollableOutputStream o => o -> IO PollableOutputStream

Methods

canPoll

data PollableOutputStreamCanPollMethodInfo

Instances

((~) * signature (m Bool), MonadIO m, IsPollableOutputStream a) => MethodInfo * PollableOutputStreamCanPollMethodInfo a signature

Methods

overloadedMethod :: MethodProxy PollableOutputStreamCanPollMethodInfo a -> signature -> s

pollableOutputStreamCanPoll

Arguments

:: (HasCallStack, MonadIO m, IsPollableOutputStream a)

=> a

stream: a PollableOutputStream.

-> m Bool

Returns: True if stream is pollable, False if not.

Checks if stream is actually pollable. Some classes may implement PollableOutputStream but have only certain instances of that class be pollable. If this method returns False, then the behavior of other PollableOutputStream methods is undefined.

For any given stream, the value returned by this method is constant; a stream cannot switch from pollable to non-pollable or vice versa.

Since: 2.28

createSource

data PollableOutputStreamCreateSourceMethodInfo

Instances

((~) * signature (Maybe b -> m Source), MonadIO m, IsPollableOutputStream a, IsCancellable b) => MethodInfo * PollableOutputStreamCreateSourceMethodInfo a signature

Methods

overloadedMethod :: MethodProxy PollableOutputStreamCreateSourceMethodInfo a -> signature -> s

pollableOutputStreamCreateSource

Arguments

:: (HasCallStack, MonadIO m, IsPollableOutputStream a, IsCancellable b)

=> a

stream: a PollableOutputStream.

-> Maybe b

cancellable: a Cancellable, or Nothing

-> m Source

Returns: a new Source

Creates a Source that triggers when stream can be written, or cancellable is triggered or an error occurs. The callback on the source is of the PollableSourceFunc type.

As with pollableOutputStreamIsWritable, it is possible that the stream may not actually be writable even after the source triggers, so you should use pollableOutputStreamWriteNonblocking rather than outputStreamWrite from the callback.

Since: 2.28

isWritable

data PollableOutputStreamIsWritableMethodInfo

Instances

((~) * signature (m Bool), MonadIO m, IsPollableOutputStream a) => MethodInfo * PollableOutputStreamIsWritableMethodInfo a signature

Methods

overloadedMethod :: MethodProxy PollableOutputStreamIsWritableMethodInfo a -> signature -> s

pollableOutputStreamIsWritable

Arguments

:: (HasCallStack, MonadIO m, IsPollableOutputStream a)

=> a

stream: a PollableOutputStream.

-> m Bool

Returns: True if stream is writable, False if not. If an error has occurred on stream, this will result in pollableOutputStreamIsWritable returning True, and the next attempt to write will return the error.

Checks if stream can be written.

Note that some stream types may not be able to implement this 100% reliably, and it is possible that a call to outputStreamWrite after this returns True would still block. To guarantee non-blocking behavior, you should always use pollableOutputStreamWriteNonblocking, which will return a IOErrorEnumWouldBlock error rather than blocking.

Since: 2.28

writeNonblocking

data PollableOutputStreamWriteNonblockingMethodInfo

Instances

((~) * signature (Maybe ByteString -> Maybe b -> m Int64), MonadIO m, IsPollableOutputStream a, IsCancellable b) => MethodInfo * PollableOutputStreamWriteNonblockingMethodInfo a signature

Methods

overloadedMethod :: MethodProxy PollableOutputStreamWriteNonblockingMethodInfo a -> signature -> s

pollableOutputStreamWriteNonblocking

Arguments

:: (HasCallStack, MonadIO m, IsPollableOutputStream a, IsCancellable b)

=> a

stream: a PollableOutputStream

-> Maybe ByteString

buffer: a buffer to write data from

-> Maybe b

cancellable: a Cancellable, or Nothing

-> m Int64

Returns: the number of bytes written, or -1 on error (including IOErrorEnumWouldBlock). (Can throw GError)

Attempts to write up to count bytes from buffer to stream, as with outputStreamWrite. If stream is not currently writable, this will immediately return IOErrorEnumWouldBlock, and you can use pollableOutputStreamCreateSource to create a Source that will be triggered when stream is writable.

Note that since this method never blocks, you cannot actually use cancellable to cancel it. However, it will return an error if cancellable has already been cancelled when you call, which may happen if you call this method after a source triggers due to having been cancelled.