From 404daac1a18eb89ba78cd007af3f974ab5e9d93e Mon Sep 17 00:00:00 2001
From: "Richard M. Stallman" <rms@gnu.org>
Date: Fri, 13 Aug 1993 22:16:38 +0000
Subject: [PATCH] (XScreenNumberOfScreen): New function.

---
 src/xfns.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/xfns.c b/src/xfns.c
index 64c58a5604f..32908d15d8d 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -3481,6 +3481,24 @@ See the documentation of `x-rebind-key' for more information.")
 #endif /* 0 */
 
 #ifdef HAVE_X11
+
+#ifndef HAVE_XSCREENNUMBEROFSCREEN
+int
+XScreenNumberOfScreen (scr)
+    register Screen *scr;
+{
+  register Display *dpy = scr->display;
+  register Screen *dpyscr = dpy->screens;
+  register int i;
+
+  for (i = 0; i < dpy->nscreens; i++, dpyscr++)
+    if (scr == dpyscr)
+      return i;
+
+  return -1;
+}
+#endif /* not HAVE_XSCREENNUMBEROFSCREEN */
+
 Visual *
 select_visual (screen, depth)
      Screen *screen;
-- 
2.39.5