# HG changeset patch
# User John W. Eaton <jwe@octave.org>
# Date 1291796704 18000
# Node ID d7fbb08e28cf3a2c1b26fe47888f28a3c5ed2c86
# Parent  71cce7108190e3b7cbfcf7ac6d7bc829e6cebd4f
strmatch.m: avoid passing length of 0 to strncmp

diff --git a/scripts/ChangeLog b/scripts/ChangeLog
--- a/scripts/ChangeLog
+++ b/scripts/ChangeLog
@@ -1,3 +1,8 @@
+2010-12-08  John W. Eaton  <jwe@octave.org>
+
+	* strings/strmatch.m: Avoid passing length of zero to strncmp.
+	Bug #31774.
+
 2010-12-07  John W. Eaton  <jwe@octave.org>
 
 	* general/repmat.m: Handle special case of replicating scalar
diff --git a/scripts/strings/strmatch.m b/scripts/strings/strmatch.m
--- a/scripts/strings/strmatch.m
+++ b/scripts/strings/strmatch.m
@@ -64,7 +64,11 @@
   exact = nargin == 3 && ischar (exact) && strcmp (exact, "exact");
 
   if (iscell (A))
-    idx = find (strncmp (s, A, len));
+    if (len > 0)
+      idx = find (strncmp (s, A, len));
+    else
+      idx = find (strcmp (s, A));
+    endif
     if (exact)
       ## We can't just use strcmp, because we need to ignore whitespace.
       B = cellfun (@strtrimr, A(idx), "uniformoutput", false);
@@ -107,4 +111,4 @@
 %!        [1; 2]);
 %!assert (strmatch ("apple pie", "apple"), []);
 %!assert (strmatch ("a b", {"a b", "a c", "c d"}));
-
+%!assert (strmatch ("", {"", "foo", "bar", ""}), [1, 4])