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School of Computer Science & Engineering
University of New South Wales
 Advanced Operating Systems 
 COMP9242 2002/S2 

Task Creation and Deletion: task_new System Call

• System has fixed number of tasks, initially all inactive.
• Inactive task is essentially a capability to create an active one.
• Task is active iff it has a valid pager.
• task_new deletes an (active or inactive) task and creates a new one
  (with task same number but different version, hence different ID).
• New task can be
  • active: syscall parameters specify start address, stack pointer,
    pager, exception handler, scheduling priority;
    • initially runs single thread (lthread 0);
  • inactive: does not consume any resources,
    can optionally be donated to new chief.