diff --git a/pcap-linux.c b/pcap-linux.c
index 17bd0f5..dc42735 100644
--- a/pcap-linux.c
+++ b/pcap-linux.c
@@ -5135,7 +5135,7 @@
 		ireq.ifr_ifrn.ifrn_name[sizeof ireq.ifr_ifrn.ifrn_name - 1] = 0;
 		ireq.u.data.length = 1;	/* 1 argument */
 		args[0] = 3;	/* request Prism header */
-		memcpy(ireq.u.name, args, IFNAMSIZ);
+		memcpy(ireq.u.name, args, sizeof (int));
 		if (ioctl(sock_fd, cmd, &ireq) != -1) {
 			/*
 			 * Success.