+#ifdef EMULATE_NNG
+ // this is only supported in nng, so behavour is different depending on the underlying library being tested
+ v = rmr_get_rcvfd( NULL );
+ errors += fail_if( v >= 0, "rmr_get_rcvfd returned a valid file descriptor when given nil context " );
+ v = rmr_get_rcvfd( rmc );
+ errors += fail_if( v < 0, "rmr_get_rcvfd did not return a valid file descriptor " );
+#else