internal/bufio/bufio.go
func (w *Writer) Flush() error {
	if w.err != nil {
		return w.err
	}
	return w.wr.Flush()
}
func (w *Writer) Flush() error {
	if w.err != nil {
		return w.err
	}
	return w.wr.Flush()
}
func ( w * Writer ) Flush ( ) error { if w . err != nil { return w . err } return w . wr . Flush ( ) }
// Flush writes any buffered data to the underlying io.Writer.
Flush writes any buffered data to the underlying io . Writer .