diff --git a/mmime.c b/mmime.c
index ab5bcf4..6334569 100644
--- a/mmime.c
+++ b/mmime.c
@@ -12,6 +12,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <time.h>
 #include <unistd.h>