diff --git a/aarg.h b/aarg.h
index a212870..907671c 100644
--- a/aarg.h
+++ b/aarg.h
@@ -5,6 +5,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <string.h>
 #include <map>
 #include <string>
 #include <sstream>
