fix ttynam for no-ttynam case

From-SVN: r27594

libf2c/ChangeLog

+Fri Jun 18 11:38:07 1999  Craig Burley  <craig@jcb-sc.com>
+
+	* libU77/ttynam_.c: if !defined (HAVE_TTYNAM),
+	write all spaces into return value instead of trying
+	to return -1 from a void function.
+
 Fri Jun 18 11:22:21 1999  Craig Burley  <craig@jcb-sc.com>
 
 	Update to Netlib version of 1999-05-10:

libf2c/libU77/ttynam_.c

@@ -59,6 +59,6 @@ extern void s_copy(register char *a, register char *b, ftnlen la, ftnlen lb);
   }
 #else
   errno = ENOSYS;
-  return -1;
+  s_copy (ret_val, " ", ret_val_len, 1);
 #endif
 }