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 gio.output_stream.OutputStream.write after this returns true would still block. To guarantee non-blocking behavior, you should always use gio.pollable_output_stream.PollableOutputStream.writeNonblocking, which will return a gio.types.IOErrorEnum.WouldBlock error rather than blocking.
The behaviour of this method is undefined if gio.pollable_output_stream.PollableOutputStream.canPoll returns false for stream.
true if stream is writable, false if not. If an error has occurred on stream, this will result in gio.pollable_output_stream.PollableOutputStream.isWritable 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 gio.output_stream.OutputStream.write after this returns true would still block. To guarantee non-blocking behavior, you should always use gio.pollable_output_stream.PollableOutputStream.writeNonblocking, which will return a gio.types.IOErrorEnum.WouldBlock error rather than blocking.
The behaviour of this method is undefined if gio.pollable_output_stream.PollableOutputStream.canPoll returns false for stream.