https://invisible-island.net/xterm/xtoolkit/
XtAppAddTimeOut, XtRemoveTimeOut - register and remove timeouts
#include <X11/Intrinsic.h>
XtIntervalId XtAppAddTimeOut(XtAppContext app_context, unsigned long
interval, XtTimerCallbackProc proc, XtPointer client_data);
void XtRemoveTimeOut(XtIntervalId timer);
app_context
Specifies the application context for which the timer is to
be set.
client_data
Specifies the argument that is to be passed to the specified
procedure when handling the callback.
interval Specifies the time interval in milliseconds.
proc Specifies the procedure that is to be called when time
expires.
timer Specifies the ID for the timeout request to be destroyed.
The XtAppAddTimeOut function creates a timeout and returns an identi-
fier for it. The timeout value is set to interval. The callback pro-
cedure is called when the time interval elapses, and then the timeout
is removed.
The XtRemoveTimeOut function removes the timeout. Note that timeouts
are automatically removed once they trigger.
XtAppAddInput(3),XtAppAddSignal(3)
X Toolkit Intrinsics – C Language Interface
Xlib - C Language X Interface
X Version 11 libXt 1.1.5.2 XtAppAddTimeOut(3)