diff --git a/lib/fko_util.c b/lib/fko_util.c
index de923657..949af84a 100644
--- a/lib/fko_util.c
+++ b/lib/fko_util.c
@@ -399,11 +399,11 @@ strtol_wrapper(const char * const str, const int min,
 }
 
 
-#ifdef WIN32
+#if defined(WIN32) || !defined(HAVE_STRNDUP)
 /* Windows does not have strndup, so we well implement it here.
  * This was the Public Domain C Library (PDCLib).
 */
-char 
+char
 *strndup( const char * s, size_t len )
 {
     char* ns = NULL;
diff --git a/lib/fko_util.h b/lib/fko_util.h
index 35d29517..9c4d3005 100644
--- a/lib/fko_util.h
+++ b/lib/fko_util.h
@@ -52,7 +52,7 @@ const char * msg_type_inttostr(const int type);
 size_t  strlcat(char *dst, const char *src, size_t siz);
 size_t  strlcpy(char *dst, const char *src, size_t siz);
 
-#ifdef WIN32
+#if defined(WIN32) || !defined(HAVE_STRNDUP)
 char * strndup( const char * s, size_t len );
 #endif