-#elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
+#elif defined __minix /* Minix */
+ return (fp->_flags & _IOWRITING) != 0;
+#elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw, NonStop Kernel */