--- a/src/DLD-FUNCTIONS/time.cc	Thu Mar 06 01:56:55 2008 -0500
+++ b/src/DLD-FUNCTIONS/time.cc	Thu Mar 06 02:27:55 2008 -0500
@@ -96,6 +96,12 @@
   return retval;
 }
 
+/*
+
+%!assert(time () > 0);
+
+*/
+
 DEFUN_DLD (gmtime, args, ,
   "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {} gmtime (@var{t})\n\
@@ -138,6 +144,28 @@
   return retval;
 }
 
+/*
+
+%!test
+%! ts = gmtime (time ());
+%! assert((isstruct (ts)
+%! && struct_contains (ts, "usec")
+%! && struct_contains (ts, "year")
+%! && struct_contains (ts, "mon")
+%! && struct_contains (ts, "mday")
+%! && struct_contains (ts, "sec")
+%! && struct_contains (ts, "min")
+%! && struct_contains (ts, "wday")
+%! && struct_contains (ts, "hour")
+%! && struct_contains (ts, "isdst")
+%! && struct_contains (ts, "yday")));
+
+%!error <Invalid call to gmtime.*> gmtime ();
+
+%!error <Invalid call to gmtime.*> gmtime (1, 2);
+
+*/
+
 DEFUN_DLD (localtime, args, ,
   "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {} localtime (@var{t})\n\
@@ -180,6 +208,28 @@
   return retval;
 }
 
+/*
+
+%!test
+%! ts = localtime (time ());
+%! assert((isstruct (ts)
+%! && struct_contains (ts, "usec")
+%! && struct_contains (ts, "year")
+%! && struct_contains (ts, "mon")
+%! && struct_contains (ts, "mday")
+%! && struct_contains (ts, "sec")
+%! && struct_contains (ts, "min")
+%! && struct_contains (ts, "wday")
+%! && struct_contains (ts, "hour")
+%! && struct_contains (ts, "isdst")
+%! && struct_contains (ts, "yday")));
+
+%!error <Invalid call to localtime.*> localtime ();
+
+%!error <Invalid call to localtime.*> localtime (1, 2);
+
+*/
+
 DEFUN_DLD (mktime, args, ,
   "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {} mktime (@var{tm_struct})\n\
@@ -219,6 +269,18 @@
   return retval;
 }
 
+/*
+
+%!test
+%! t = time ();
+%! assert(fix (mktime (localtime (t))) == fix (t));
+
+%!error <Invalid call to mktime.*> mktime ();
+
+%!error <Invalid call to mktime.*> mktime (1, 2, 3);
+
+*/
+
 DEFUN_DLD (strftime, args, ,
   "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {} strftime (@var{fmt}, @var{tm_struct})\n\
@@ -403,6 +465,20 @@
   return retval;
 }
 
+/*
+
+%!assert((isstr (strftime ("%%%n%t%H%I%k%l", localtime (time ())))
+%! && isstr (strftime ("%M%p%r%R%s%S%T", localtime (time ())))
+%! && isstr (strftime ("%X%Z%z%a%A%b%B", localtime (time ())))
+%! && isstr (strftime ("%c%C%d%e%D%h%j", localtime (time ())))
+%! && isstr (strftime ("%m%U%w%W%x%y%Y", localtime (time ())))));
+
+%!error <Invalid call to strftime.*> strftime ();
+
+%!error <Invalid call to strftime.*> strftime ("foo", localtime (time ()), 1);
+
+*/
+
 DEFUN_DLD (strptime, args, ,
  "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {[@var{tm_struct}, @var{nchars}] =} strptime (@var{str}, @var{fmt})\n\