Define the process control block(OS-4)

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Process control block


-Each process is represented in the operating system by the process control block also called as task control block.
-It contains many pieces of information associated with a specific process include these

Process states:

The state may be new/ready,running,waiting,haltered and soon.

Program counter:

The counter can be indicate to the address of the next instruction to be executed for this process.

CPU registers:

The register vary in number and type depending in the computer or architecture .they includes the accumulator,index register,stack pointer , general purpose of register.

Memory management information:

It may be includes such information as the value of the base and limit register, the page tables or segment tables depending on the memory system used by the operating system.

Accounting information:

It includes the account of the CPU and real time used,time limits account number,job or process number and soon.

I/O status information:

-It includes the list of the i/o device information allocated to the process, list of open file and soon

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