diff --git a/src/blockchain_utilities/blockchain_import.cpp b/src/blockchain_utilities/blockchain_import.cpp
index a58257719..9e2c97bd0 100644
--- a/src/blockchain_utilities/blockchain_import.cpp
+++ b/src/blockchain_utilities/blockchain_import.cpp
@@ -33,6 +33,7 @@
 
 #include <boost/filesystem.hpp>
 #include <boost/algorithm/string.hpp>
+#include <unistd.h>
 #include "misc_log_ex.h"
 #include "bootstrap_file.h"
 #include "bootstrap_serialization.h"