https://invisible-island.net/xterm/xtoolkit/
XtSetMultiClickTime, XtGetMultiClickTime - set and get multi-click
times
#include <X11/Intrinsic.h>
void XtSetMultiClickTime(Display* display, int time);
int XtGetMultiClickTime(Display* display);
display Specifies the display connection.
time Specifies the multi-click time in milliseconds.
XtSetMultiClickTime sets the time interval used by the translation man-
ager to determine when multiple events are interpreted as a repeated
event.
XtGetMultiClickTime returns the time in milliseconds that the transla-
tion manager uses to determine if multiple events are to be interpreted
as a repeated event for purposes of matching a translation entry con-
taining a repeat count.
X Toolkit Intrinsics – C Language Interface
Xlib - C Language X Interface
X Version 11 libXt 1.1.5.2 XtSetMultiClickTime(3)