diff --git a/sndiod/sndiod.c b/sndiod/sndiod.c
index 12685f2..a8381ae 100644
--- a/sndiod/sndiod.c
+++ b/sndiod/sndiod.c
@@ -98,6 +98,7 @@ void unsetsig(void);
 void privdrop(void);
 struct dev *mkdev(char *, struct aparams *,
     int, int, int, int, int, int);
+struct port *mkport(char *, int);
 struct opt *mkopt(char *, struct dev *,
     int, int, int, int, int, int, int, int);