diff --git a/man2/eventfd.2 b/man2/eventfd.2
index 929234ab7..71e9d85b4 100644
--- a/man2/eventfd.2
+++ b/man2/eventfd.2
@@ -386,6 +386,7 @@ Parent read 28 (0x1c) from efd
 .EX
 #include <sys/eventfd.h>
 #include <unistd.h>
+#include <inttypes.h>           /* Definition of PRIu64 & PRIx64 */
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdint.h>             /* Definition of uint64_t */
@@ -430,8 +431,7 @@ main(int argc, char *argv[])
         s = read(efd, &u, sizeof(uint64_t));
         if (s != sizeof(uint64_t))
             handle_error("read");
-        printf("Parent read %llu (0x%llx) from efd\en",
-                (unsigned long long) u, (unsigned long long) u);
+        printf("Parent read %"PRIu64" (0x%"PRIx64") from efd\en", u, u);
         exit(EXIT_SUCCESS);
 
     case \-1: