diff -urN ref/include/linux/sched.h tuxsched/include/linux/sched.h
--- ref/include/linux/sched.h	Sat Apr 28 20:29:48 2001
+++ tuxsched/include/linux/sched.h	Sun Apr 29 17:31:18 2001
@@ -396,6 +396,10 @@
 	int (*notifier)(void *priv);
 	void *notifier_data;
 	sigset_t *notifier_mask;
+
+	/* TUX state */
+	void *tux_info;
+	void (*tux_exit)(void);
 	
 /* Thread group tracking */
    	u32 parent_exec_id;
diff -urN ref/kernel/exit.c tuxsched/kernel/exit.c
--- ref/kernel/exit.c	Sat Apr 28 18:37:45 2001
+++ tuxsched/kernel/exit.c	Sun Apr 29 17:30:54 2001
@@ -439,6 +439,13 @@
 #ifdef CONFIG_BSD_PROCESS_ACCT
 	acct_process(code);
 #endif
+	if (current->tux_info) {
+#ifdef CONFIG_TUX_DEBUG
+		printk("Possibly unexpected TUX-thread exit(%ld) at %p?\n",
+			code, __builtin_return_address(0));
+#endif
+		current->tux_exit();
+	}
 	__exit_mm(tsk);
 
 	lock_kernel();
diff -urN ref/kernel/fork.c tuxsched/kernel/fork.c
--- ref/kernel/fork.c	Sat Apr 28 18:37:45 2001
+++ tuxsched/kernel/fork.c	Sun Apr 29 17:30:54 2001
@@ -574,6 +574,7 @@
 		goto fork_out;
 
 	*p = *current;
+	p->tux_info = NULL;
 
 	retval = -EAGAIN;
 	if (atomic_read(&p->user->processes) >= p->rlim[RLIMIT_NPROC].rlim_cur)