Request an asynchronous write of count bytes from buffer into the stream. When the operation is finished callback will be called. You can then call OutputStream.writeFinish to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in G_IO_ERROR_PENDING errors.

A value of count larger than G_MAXSSIZE will cause a G_IO_ERROR_INVALID_ARGUMENT error.

On success, the number of bytes written will be passed to the callback. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial I/O error, but generally we try to write as many bytes as requested.

You are guaranteed that this method will never fail with G_IO_ERROR_WOULD_BLOCK - if stream can't accept more data, the method will just wait until this changes.

Any outstanding I/O request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is G_PRIORITY_DEFAULT.

The asynchronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

For the synchronous, blocking version of this function, see OutputStream.write.

Note that no copy of buffer will be made, so it must stay valid until callback is called. See OutputStream.writeBytesAsync for a glib.Bytes version that will automatically hold a reference to the contents (without copying) for the duration of the call.

class OutputStream


buffer ubyte[]

the buffer containing the data to write.

ioPriority int

the io priority of the request.

cancellable Cancellable

optional gio.Cancellable object, NULL to ignore.

callback GAsyncReadyCallback

callback to call when the request is satisfied

userData void*

the data to pass to callback function