+#include <errno.h>
+#include <unistd.h>
+
+#include "freading.h"
+
+#include "stdio-impl.h"
+
+#include "unused-parameter.h"
+
+#undef fflush
+
+
+#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+
+/* Clear the stream's ungetc buffer, preserving the value of ftello (fp). */
+static inline void
+clear_ungetc_buffer_preserving_position (FILE *fp)
+{
+ if (fp->_flags & _IO_IN_BACKUP)
+ /* _IO_free_backup_area is a bit complicated. Simply call fseek. */
+ fseeko (fp, 0, SEEK_CUR);
+}
+
+#else
+
+/* Clear the stream's ungetc buffer. May modify the value of ftello (fp). */
+static inline void
+clear_ungetc_buffer (FILE *fp)
+{
+# if defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin */
+ if (HASUB (fp))
+ {
+ fp_->_p += fp_->_r;
+ fp_->_r = 0;
+ }
+# elif defined __EMX__ /* emx+gcc */
+ if (fp->_ungetc_count > 0)
+ {
+ fp->_ungetc_count = 0;
+ fp->_rcount = - fp->_rcount;
+ }
+# elif defined _IOERR /* Minix, AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw, NonStop Kernel */
+ /* Nothing to do. */
+# else /* other implementations */
+ fseeko (fp, 0, SEEK_CUR);
+# endif
+}
+