diff --git a/ui-ssdiff.c b/ui-ssdiff.c
index 68c2044..a3dd059 100644
--- a/ui-ssdiff.c
+++ b/ui-ssdiff.c
@@ -103,8 +103,7 @@
 		return 0;
 	len = buf2 - buf1;
 	buf2 = xmalloc(len + 1);
-	strncpy(buf2, buf1, len);
-	buf2[len] = '\0';
+	strlcpy(buf2, buf1, len + 1);
 	res = atoi(buf2);
 	free(buf2);
 	return res;