diff --git a/src/engine/fileunix.c b/src/engine/fileunix.c
index 34d440efb..1ac471b9b 100644
--- a/src/engine/fileunix.c
+++ b/src/engine/fileunix.c
@@ -35,6 +35,7 @@
 
 #include <assert.h>
 #include <stdio.h>
+#include <sys/stat.h>  /* needed for mkdir() */
 
 #if defined( sun ) || defined( __sun ) || defined( linux )
 # include <unistd.h>  /* needed for read and close prototype */