Tcl Library Procedures
Tcl_CreateTimerHandler, Tcl_DeleteTimerHandler - call a procedure at a
Tcl_CreateTimerHandler(milliseconds, proc, clientData)
int milliseconds (in)
How many milliseconds to wait before invoking proc.
Tcl_TimerProc *proc (in)
Procedure to invoke after milliseconds have elapsed.
ClientData clientData (in)
Arbitrary one-word value to pass to proc.
Tcl_TimerToken token (in)
Token for previously-created timer handler (the return value
from some previous call to Tcl_CreateTimerHandler).
Tcl_CreateTimerHandler arranges for proc to be
invoked at a time milliseconds milliseconds in the
The callback to proc will be made by Tcl_DoOneEvent,
so Tcl_CreateTimerHandler is only useful in programs that
dispatch events through Tcl_DoOneEvent or through Tcl commands
such as vwait.
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 Tcl_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 Tcl_TimerProc:
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 application-specific information about
what to do in proc.
typedef void Tcl_TimerProc(ClientData clientData);
Tcl_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 Tcl_DeleteTimerHandler does nothing.
The tokens returned by Tcl_CreateTimerHandler never have
a value of NULL, so if NULL is passed to Tcl_DeleteTimerHandler
then the procedure does nothing.
callback, clock, handler, timer
Last change: 7.5
[ tcl8.0a1 | tk8.0a1 | X-ref ]
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