diff --git a/alsactl/lock.c b/alsactl/lock.c
index 64bdaff..70fb6cf 100644
--- a/alsactl/lock.c
+++ b/alsactl/lock.c
@@ -31,6 +31,7 @@
 #include <sys/time.h>
 #include <sys/stat.h>
 #include "alsactl.h"
+#include "os_compat.h"
 
 #define PATH_SIZE 512