gtk:notebook-tab-label (notebook child)

notebook -- a gtk:notebook widget
child -- a gtk:widget child page
tab -- a gtk:widget object for the notebook tab label to use, or nil for default notebook tab label

Gets or sets the notebook tab label for the page child. The nil value is returned if the child is not in the notebook or if no notebook tab label has been set for the child. If the nil value is specified for tab, then the page will have the label 'page N'.