/* SystemV derived implementations. */
+#ifdef __TANDEM /* NonStop Kernel */
+# ifndef _IOERR
+/* These values were determined by the program 'stdioext-flags' at
+ <http://lists.gnu.org/archive/html/bug-gnulib/2010-12/msg00165.html>. */
+# define _IOERR 0x40
+# define _IOREAD 0x80
+# define _IOWRT 0x4
+# define _IORW 0x100
+# endif
+#endif
+
#if defined _IOERR
# if defined __sun && defined _LP64 /* Solaris/{SPARC,AMD64} 64-bit */