diff --git a/src/structures.h b/src/structures.h
index 7ae0197..83c652a 100644
--- a/src/structures.h
+++ b/src/structures.h
@@ -28,6 +28,7 @@ extern "C" {
 #ifndef _WIN32
 #include <sys/socket.h>
 #include <netinet/in.h>
+#include <netinet/tcp.h>
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <pthread.h>