diff --git a/fcgi/libfcgi/fcgio.cpp b/fcgi/libfcgi/fcgio.cpp

index 95e28ca..c93e46d 100644

--- a/fcgi/libfcgi/fcgio.cpp

+++ b/fcgi/libfcgi/fcgio.cpp

@@ -24,6 +24,7 @@

 #include <limits.h>

 #include "fcgio.h"

+#include <cstdio>

 using std::streambuf;

 using std::istream;