This ensures that if there is an error in the definition of the
PENDING_OUTPUT_N_BYTES expression, we'll find about it right away;
that value is used only in the rare event that close_stdout's
fclose fails with EBADF.
--- /dev/null
+/* Ensure that __fpending works. */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "__fpending.h"
+
+int
+main ()
+{
+ if (__fpending (stdout) != 0)
+ abort ();
+
+ fputs ("foo", stdout);
+ if (__fpending (stdout) != 3)
+ abort ();
+
+ fflush (stdout);
+ if (__fpending (stdout) != 0)
+ abort ();
+
+ exit (0);
+}