HPUX TimerHndlr[3]

 Tk_CreateTimerHandler(3)            Tk             Tk_CreateTimerHandler(3)

 Tk Library Procedures                                 Tk Library Procedures





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 NAME
      Tk_CreateTimerHandler, Tk_DeleteTimerHandler - call a procedure  at  a
      given time

 SYNOPSIS
      #include <tk.h>

      Tk_TimerToken
      Tk_CreateTimerHandler(milliseconds, proc, clientData)

      Tk_DeleteTimerHandler(token)

 ARGUMENTS
      int             milliseconds   (in)      How many milliseconds to wait
                                               before invoking proc.

      Tk_TimerProc    *proc          (in)       Procedure  to  invoke  after
                                               milliseconds have elapsed.

      ClientData      clientData     (in)      Arbitrary one-word  value  to
                                               pass to proc.

      Tk_TimerToken   token          (in)      Token for  previously-created
                                               timer   handler  (the  return
                                               value from some previous call
                                               to Tk_CreateTimerHandler).
 ___________________________________________________________________________


 DESCRIPTION
      Tk_CreateTimerHandler arranges for  proc  to  be  invoked  at  a  time
      milliseconds milliseconds in the future.  The callback to proc will be
      made by Tk_DoOneEvent, so  Tk_CreateTimerHandler  is  only  useful  in
      programs  that  dispatch events through Tk_DoOneEvent or through other
      Tk procedures that call Tk_DoOneEvent, such as Tk_MainLoop.  The  call
      to  proc  may not be made at the exact time given by milliseconds:  it
      will be made at the next opportunity after that time.  For example, if
      Tk_DoOneEvent  isn't  called until long after the time has elapsed, or
      if there are other pending events to process before the call to  proc,
      then the call to proc will be delayed.

      Proc should have arguments  and  return  value  that  match  the  type
      Tk_TimerProc:
           typedef void Tk_TimerProc(ClientData clientData);
      The clientData parameter to proc is a copy of the clientData  argument
      given   to  Tcl_CreateTimerHandler  when  the  callback  was  created.
      Typically,  clientData  points  to   a   data   structure   containing



                                    - 1 -        Formatted:  August 11, 1996






 Tk_CreateTimerHandler(3)            Tk             Tk_CreateTimerHandler(3)

 Tk Library Procedures                                 Tk Library Procedures





      application-specific information about what to do in proc.

      Tk_DeleteTimerHandler may be called  to  delete  a  previously-created
      timer  handler.   It deletes the handler indicated by token so that no
      call to proc will be made;  if that handler  no  longer  exists  (e.g.
      because the time period has already elapsed and proc has been invoked)
      then Tk_DeleteTimerHandler does nothing.


 KEYWORDS
      callback, clock, handler, timer









































                                    - 2 -        Formatted:  August 11, 1996