diff --git a/crypto/rand/rand_unix.c b/crypto/rand/rand_unix.c
--- rand_unix.c	2019-09-10 16:24:10.000000000 +0300
+++ rand_unix_b.c	2020-01-26 15:34:21.226177000 +0300
@@ -109,6 +109,7 @@
  *
  */
 #include <stdio.h>
+#include <fd_set.h>
 
 #define USE_SOCKETS
 #include "e_os.h"