diff --git a/src/pki.c b/src/pki.c
index aa32fc4a..50c61877 100644
--- a/src/pki.c
+++ b/src/pki.c
@@ -33,6 +33,7 @@
 #include "config.h"
 
 #include <errno.h>
+#include <stdio.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>