diff --git a/lib/log.h b/lib/log.h
index 77cd53b..514884c 100644
--- a/lib/log.h
+++ b/lib/log.h
@@ -189,6 +189,8 @@
 extern size_t quagga_timestamp(int timestamp_precision /* # subsecond digits */,
 			       char *buf, size_t buflen);
 
+extern void zlog_hexdump(void *mem, unsigned int len);
+
 /* structure useful for avoiding repeated rendering of the same timestamp */
 struct timestamp_control {
    size_t len;		/* length of rendered timestamp */