Tk_MainLoop - loop for events until all windows are deleted

Tk_MainLoop  is a procedure that loops repeatedly calling Tcl_DoOneEvent.  It returns only when there are
       no applications left in this process (i.e. no main windows exist anymore).  Most  windowing  applications
       will  call  Tk_MainLoop after initialization; the main execution of the application will consist entirely
       of callbacks invoked via Tcl_DoOneEvent.

       application, event, main loop

Tk                                                                                              Tk_MainLoop(3tk)

       Tk_MainLoop - loop for events until all windows are deleted

#include<tk.h>Tk_MainLoop()
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