diff --git a/src/steamcompmgr.cpp b/src/steamcompmgr.cpp
index 35ccf8e..f464a50 100644
--- a/src/steamcompmgr.cpp
+++ b/src/steamcompmgr.cpp
@@ -39,6 +39,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <fcntl.h>
 #include <math.h>
 #include <sys/poll.h>
 #include <sys/time.h>