diff --git a/surf.c b/surf.c
index f2170a4..d423cf1 100644
--- a/surf.c
+++ b/surf.c
@@ -12,6 +12,7 @@
 #include <string.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include <limits.h>
 #include <stdlib.h>