+ int event_number, error_number;
+ if (!DPMSQueryExtension(si->dpy, &event_number, &error_number) ||
+ !DPMSCapable(si->dpy))
+ {
+ if (si->prefs.verbose_p)
+ fprintf (stderr,
+ "%s: unable to power %s monitor: no DPMS extension.\n",
+ blurb(), (on_p ? "on" : "off"));
+ return;
+ }
+
+ DPMSForceLevel(si->dpy, (on_p ? DPMSModeOn : DPMSModeOff));