Tk_SetClass, Tk_Class - set or retrieve a window's class


       #include <tk.h>

       Tk_SetClass(tkwin, class)



       Tk_Window   tkwin    (in)      Token for window.

       char        *class   (in)      New  class name for window.


       Tk_SetClass is called to associate a class with a particu­
       lar  window.   The class string identifies the type of the
       window;  all windows with the same general class of behav­
       ior  (button,  menu, etc.) should have the same class.  By
       convention all class names start with  a  capital  letter,
       and  there exists a Tcl command with the same name as each
       class (except all in lower-case) which can be used to cre­
       ate  and  manipulate  windows  of  that class.  A window's
       class string is initialized to NULL  when  the  window  is

       For main windows, Tk automatically propagates the name and
       class to the WM_CLASS property used  by  window  managers.
       This happens either when a main window is actually created
       (e.g.  in  Tk_MakeWindowExist),  or  when  Tk_SetClass  is
       called,  whichever occurs later.  If a main window has not
       been assigned a class then Tk will not  set  the  WM_CLASS
       property for the window.

       Tk_Class  is  a  macro  that  returns the current value of
       tkwin's class.  The value is returned as a  Tk_Uid,  which
       may  be  used  just like a string pointer but also has the
       properties of a unique identifier (see  the  manual  entry
       for  Tk_GetUid  for  details).   If tkwin has not yet been
       given a class, then Tk_Class will return NULL.


       class, unique identifier, window, window manager