Creates a GSource that triggers when stream can be written, or
cancellable is triggered or an error occurs. The callback on the
source is of the GPollableSourceFunc type.
As with g_pollable_output_stream_is_writable(), it is possible that
the stream may not actually be writable even after the source
triggers, so you should use g_pollable_output_stream_write_nonblocking()
rather than g_output_stream_write() from the callback.
Since 2.28
Creates a GSource that triggers when stream can be written, or cancellable is triggered or an error occurs. The callback on the source is of the GPollableSourceFunc type. As with g_pollable_output_stream_is_writable(), it is possible that the stream may not actually be writable even after the source triggers, so you should use g_pollable_output_stream_write_nonblocking() rather than g_output_stream_write() from the callback. Since 2.28