+ /*
+ * Ensure that fds 0, 1, 2 are open, to /dev/null if nowhere else.
+ * This way we can close 0, 1, 2 in detach() without clobbering
+ * a fd that we are using.
+ */
+ if ((i = open("/dev/null", O_RDWR)) >= 0) {
+ while (0 <= i && i <= 2)
+ i = dup(i);
+ if (i >= 0)
+ close(i);
+ }
+