+#include <sys/socket.h>
+
+#if SIZEOF_PID_T == 4
+# define PID_FMT "%" PRIu32
+#elif SIZEOF_PID_T == 2
+# define PID_FMT "%" PRIu16
+#else
+# error Unknown pid_t size
+#endif
+
+#if SIZEOF_UID_T == 4
+# define UID_FMT "%" PRIu32
+#elif SIZEOF_UID_T == 2
+# define UID_FMT "%" PRIu16
+#else
+# error Unknown uid_t size
+#endif