diff --git a/acountry.c b/acountry.c
index e7029c8a..14efa072 100644
--- a/acountry.c
+++ b/acountry.c
@@ -43,6 +43,9 @@
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
 
 #if defined(WIN32)
   #include <winsock.h>
diff --git a/adig.c b/adig.c
index f7f601ce..59325fe6 100644
--- a/adig.c
+++ b/adig.c
@@ -32,6 +32,9 @@
 #endif
 #include <netdb.h>
 #endif
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
 
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/ahost.c b/ahost.c
index 974f94d6..a5f8fb5a 100644
--- a/ahost.c
+++ b/ahost.c
@@ -29,6 +29,9 @@
 #include <unistd.h>
 #endif
 #endif
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
 
 #include <stdio.h>
 #include <stdlib.h>