--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/transient.c	Wed Apr 02 20:32:11 2014 +0400
@@ -0,0 +1,42 @@
+/* cc transient.c -o transient -lX11 */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+int main(void) {
+	Display *d;
+	Window r, f, t = None;
+	XSizeHints h;
+	XEvent e;
+
+	d = XOpenDisplay(NULL);
+	if (!d)
+		exit(1);
+	r = DefaultRootWindow(d);
+
+	f = XCreateSimpleWindow(d, r, 100, 100, 400, 400, 0, 0, 0);
+	h.min_width = h.max_width = h.min_height = h.max_height = 400;
+	h.flags = PMinSize | PMaxSize;
+	XSetWMNormalHints(d, f, &h);
+	XStoreName(d, f, "floating");
+	XMapWindow(d, f);
+
+	XSelectInput(d, f, ExposureMask);
+	while (1) {
+		XNextEvent(d, &e);
+
+		if (t == None) {
+			sleep(5);
+			t = XCreateSimpleWindow(d, r, 50, 50, 100, 100, 0, 0, 0);
+			XSetTransientForHint(d, t, f);
+			XStoreName(d, t, "transient");
+			XMapWindow(d, t);
+			XSelectInput(d, t, ExposureMask);
+		}
+	}
+
+	XCloseDisplay(d);
+	exit(0);
+}