+struct thread *switch_threads (struct thread *cur, struct thread *next);
+
+/* Stack frame for switch_entry(). */
+struct switch_entry_frame
+ {
+ void (*eip) (void);
+ };
+
+void switch_entry (void);
+
+/* Pops the CUR and NEXT arguments off the stack, for use in
+ initializing threads. */
+void switch_thunk (void);