Fix bug that can cause a SIGSEGV.

diff --git a/v7/src/edwin/key-x11.scm b/v7/src/edwin/key-x11.scm
index cf42fa1b8d78778509ea07c987402b4d167700c1..64f932072cb4447d036a3b4666769922085c80de 100644 (file)
--- a/v7/src/edwin/key-x11.scm
+++ b/v7/src/edwin/key-x11.scm
@@ -1,8 +1,8 @@
 ;;; -*-Scheme-*-
 ;;;
-;;;    $Id: key-x11.scm,v 1.3 1995/04/13 23:28:37 cph Exp $
+;;;    $Id: key-x11.scm,v 1.4 1996/10/24 16:14:04 cph Exp $
 ;;;
-;;;    Copyright (c) 1991-95 Massachusetts Institute of Technology
+;;;    Copyright (c) 1991-96 Massachusetts Institute of Technology
 ;;;
 ;;;    This material was developed by the Scheme project at the
 ;;;    Massachusetts Institute of Technology, Department of
@@ -48,10 +48,12 @@
                    bucky-bits))
 
 (define (keysym->name keysym)
-  (cdr (vector-binary-search x-key-translation-table
-                            (lambda (u v) (< u v))
-                            (lambda (pair) (car pair))
-                            keysym)))
+  (let ((entry
+        (vector-binary-search x-key-translation-table
+                              (lambda (u v) (< u v))
+                              (lambda (pair) (car pair))
+                              keysym)))
+    (and entry (cdr entry))))
 
 ;; This table is a simple translation of /usr/include/X11/keysym.h.
 ;; However, that the vendor-specific marker (bit 28, numbered from 0)