+
+#if defined(OPENSSL_NO_POSIX_IO)
+/*
+ * One can argue that one should implement dummy placeholder for
+ * BIO_s_fd here...
+ */
+#else
+/*
+ * As for unconditional usage of "UPLINK" interface in this module.
+ * Trouble is that unlike Unix file descriptors [which are indexes
+ * in kernel-side per-process table], corresponding descriptors on
+ * platforms which require "UPLINK" interface seem to be indexes
+ * in a user-land, non-global table. Well, in fact they are indexes
+ * in stdio _iob[], and recall that _iob[] was the very reason why
+ * "UPLINK" interface was introduced in first place. But one way on
+ * another. Neither libcrypto or libssl use this BIO meaning that
+ * file descriptors can only be provided by application. Therefore
+ * "UPLINK" calls are due...
+ */
+#include "bio_lcl.h"