diff --git a/gnu/lib/libdialog/prgbox.c b/gnu/lib/libdialog/prgbox.c
index 80f6ff52d091..10d39e4bf110 100644
--- a/gnu/lib/libdialog/prgbox.c
+++ b/gnu/lib/libdialog/prgbox.c
@@ -16,9 +16,13 @@
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $FreeBSD$
  */
 
 
+#include <sys/types.h>
+
 #include <dialog.h>
 #include <errno.h>
 #include <sys/wait.h>