--- a/dnstracer.c

+++ b/dnstracer.c

@@ -1619,7 +1619,7 @@

     if (argv[0] == NULL) usage();

     // check for a trailing dot

-    strcpy(argv0, argv[0]);

+    strncpy(argv0, argv[0], NS_MAXDNAME);

     if (argv0[strlen(argv[0]) - 1] == '.') argv0[strlen(argv[0]) - 1] = 0;

     printf("Tracing to %s[%s] via %s, maximum of %d retries\n",