code: func (v *Statusbar) Push(contextID uint, text string) uint {
  	cstr := C.CString(text)
  	defer C.free(unsafe.Pointer(cstr))
  	c := C.gtk_statusbar_push(v.native(), C.guint(contextID),
  		(*C.gchar)(cstr))
  	return uint(c)
  }
docs: // Push() is a wrapper around gtk_statusbar_push().