+ + (fp->_Mode & 0x4000 /* _MBYTE */
+ ? (fp->_Back + sizeof (fp->_Back)) - fp->_Rback
+ : 0);
+#elif defined __MINT__ /* Atari FreeMiNT */
+ if (!fp->__mode.__read)
+ return 0;
+ return (fp->__pushed_back
+ ? fp->__get_limit - fp->__pushback_bufp + 1
+ : fp->__get_limit - fp->__bufp);
+#elif defined SLOW_BUT_NO_HACKS /* users can define this */
+ abort ();
+ return 0;