diff --git a/nbase/nbase.h b/nbase/nbase.h
index 6725e9a59..462bfe964 100644
--- a/nbase/nbase.h
+++ b/nbase/nbase.h
@@ -337,6 +337,38 @@ extern "C" int vsnprintf (char *, size_t, const char *, va_list);
 #endif
 
 
+#ifdef WIN32
+#define CHECKED_FD_SET FD_SET
+#else
+#define CHECKED_FD_SET(fd, set) \
+  do { \
+    if ((fd) < FD_SETSIZE) { \
+      FD_SET((fd), (set)); \
+    } else { \
+      fprintf(stderr, "%s:%ld: Attempt to FD_SET fd %d, which is not less than" \
+        " FD_SETSIZE (%d). Try using a lower parallelism.", \
+        __FILE__, (long int) __LINE__, (fd), FD_SETSIZE); \
+      abort(); \
+    } \
+  } while (0)
+#endif
+
+#ifdef WIN32
+#define CHECKED_FD_CLR FD_CLR
+#else
+#define CHECKED_FD_CLR(fd, set) \
+  do { \
+    if ((fd) < FD_SETSIZE) { \
+      FD_CLR((fd), (set)); \
+    } else { \
+      fprintf(stderr, "%s:%ld: Attempt to FD_CLR fd %d, which is not less than" \
+        " FD_SETSIZE (%d). Try using a lower parallelism.", \
+        __FILE__, (long int) __LINE__, (fd), FD_SETSIZE); \
+      abort(); \
+    } \
+  } while (0)
+#endif
+
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/nsock/src/engine_select.c b/nsock/src/engine_select.c
index 6fedb74ee..44ef65fe4 100644
--- a/nsock/src/engine_select.c
+++ b/nsock/src/engine_select.c
@@ -68,38 +68,6 @@
 #include "nsock_pcap.h"
 #endif
 
-#ifdef WIN32
-#define CHECKED_FD_SET FD_SET
-#else
-#define CHECKED_FD_SET(fd, set) \
-  do { \
-    if ((fd) < FD_SETSIZE) { \
-      FD_SET((fd), (set)); \
-    } else { \
-      fprintf(stderr, "%s:%ld: Attempt to FD_SET fd %d, which is not less than" \
-        " FD_SETSIZE (%d). Try using a lower parallelism.", \
-        __FILE__, (long int) __LINE__, (fd), FD_SETSIZE); \
-      abort(); \
-    } \
-  } while (0)
-#endif
-
-#ifdef WIN32
-#define CHECKED_FD_CLR FD_CLR
-#else
-#define CHECKED_FD_CLR(fd, set) \
-  do { \
-    if ((fd) < FD_SETSIZE) { \
-      FD_CLR((fd), (set)); \
-    } else { \
-      fprintf(stderr, "%s:%ld: Attempt to FD_CLR fd %d, which is not less than" \
-        " FD_SETSIZE (%d). Try using a lower parallelism.", \
-        __FILE__, (long int) __LINE__, (fd), FD_SETSIZE); \
-      abort(); \
-    } \
-  } while (0)
-#endif
-
 
 /* --- ENGINE INTERFACE PROTOTYPES --- */
 static int select_init(mspool *nsp);