# HG changeset patch
# User John W. Eaton <jwe@octave.org>
# Date 1287813891 14400
# Node ID 461ae8d58cdb7bbdedb9f4230d7f348409e8f1cd
# Parent  195cffc2d0a39e065ecf48821a674d23aa3e11f5
tests for is_valid_file_id

diff --git a/scripts/ChangeLog b/scripts/ChangeLog
--- a/scripts/ChangeLog
+++ b/scripts/ChangeLog
@@ -1,3 +1,8 @@
+2010-10-23  John W. Eaton  <jwe@octave.org>
+
+	* io/is_valid_file_id.m: Ensure that FID is a scalar before
+	calling fopen to get info.  New tests.
+
 2010-10-23  John W. Eaton  <jwe@octave.org>
 
 	* io/is_valid_file_id.m: New function.
diff --git a/scripts/io/is_valid_file_id.m b/scripts/io/is_valid_file_id.m
--- a/scripts/io/is_valid_file_id.m
+++ b/scripts/io/is_valid_file_id.m
@@ -28,11 +28,19 @@
 
   if (nargin == 1)
     try
-      [file, mode, arch] = fopen (fid);
-      retval = ! isempty (file);
+      if (isscalar (fid))
+        [file, mode, arch] = fopen (fid);
+        retval = ! isempty (file);
+      endif
     end_try_catch
   else
     print_usage ();
   endif
 
 endfunction
+
+%!assert (is_valid_file_id (stdout))
+%!assert (! is_valid_file_id ([1,2;3,4]))
+%!assert (! is_valid_file_id ("not_a_file_id"))
+%!assert (! is_valid_file_id (-1))
+%!assert (! is_valid_file_id (pi))