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Process's hierarchy in operating system-computer world

Process's hierarchy in operating system-computer world

Process's hierarchy : 

In operating system process are arranged in a hierarchical manner. Some process are controlling some another process these process are called parent process. In other word we can say that modern operating system are used to create or destroyed process. The creating process is known as parent process and the new process are called child process. A parent process have many child process but the child process has only one parent process. 

Hierarchical structure :
The operating system is designed in a manner that a parent process has the block of a child process each child is ultimately under the full control of parent process and this structure is called the hierarchical structure of the process existing in a system.  
 Modern general purpose operating system permit a user to create and destroy processes
  1.  In Unix this is done by the the fork system call.
  2.  After a fork both parent and child keep running and each can fork of other process.
  3. The root of the tree is a special process created by the operating system.

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