diff --git a/dirtycow.c b/dirtycow.c
index fed0ecc..423e92d 100644
--- a/dirtycow.c
+++ b/dirtycow.c
@@ -1,4 +1,5 @@
 #include <err.h>
+#include <errno.h>
 #include <assert.h>
 #include <dlfcn.h>
 #include <stdio.h>
@@ -306,4 +307,4 @@ int dcow(int argc, const char * argv[])
 	}
 
 	return 0;
-}
\ No newline at end of file
+}