Retrive the text string of widget if it is a GtkLabel, GtkEditable (entry and text widgets) or GtkTextView. Since 2.14
valid widget pointer.
new 0-terminated C string, needs to be released with g_free().
See Implementation
Retrive the text string of widget if it is a GtkLabel, GtkEditable (entry and text widgets) or GtkTextView. Since 2.14