public async ssize_t write_async (uint8 buffer, Cancellable? cancellable) throws Error
Request an asynchronous write of count bytes from
buffer into the this.
When the operation is finished
callback will be called. You can then call
port_write_async.end to get the result of the operation.
the buffer containing the data to write
optional GCancellable object, NULL to ignore
callback to call when the request is satisfied
the number of bytes to write
the data to pass to callback function