CITS2002 Systems Programming  
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Process States

We can view the process from two points of view: that of the processor, and that of the process itself.

  • The processor's view is simple: the processor's only role is to execute machine instructions from main memory. Over time, the processor continually executes the sequence of instructions indicated by the program counter (PC).

    The processor is unaware that different sequences of instructions have a logical existence, that different sequences under execution are referred to as processes or tasks.

  • From the process's point of view, it is either being executed by the processor, or it is waiting to be executed (for simplicity here, we consider that a terminated process no longer exists).

We've already identified two possible process states that a process may be in at any one time: Running and Ready.

Question: Can a process determine in what state it is?

 


CITS2002 Systems Programming, Lecture 7, p2, 14th August 2023.