+#ifdef SYSIO_TRACING
+ /*
+ * tracing
+ */
+ arg = getenv("SYSIO_TRACING");
+ err = _sysio_boot("trace", arg);
+ if (err)
+ return err;
+#endif
+ /*
+ * namespace
+ */
+ arg = getenv("SYSIO_NAMESPACE");
+ if (!(arg || (arg = getenv("SYSIO_MANUAL")))) {
+ /*
+ * Assume a native mount at root with automounts enabled.
+ */
+ arg = "{mnt,dev=\"native:/\",dir=/,fl=2}";
+ }
+ err = _sysio_boot("namespace", arg);