3.) OPERATION PROCESS

A.) PROCESS ON CREATION
Parent process creates children processes, which, in turn create other processes, forming a tree of processes.

Resource sharing:

>Parent and children share all resources.
>Children share subset of parent’s resources.
>Parent and child share no resources.

Execution:

>Parent and children execute concurrently.
>Parent waits until children terminate.

B.) PROCESS TERMINATION

>Process executes last statement and asks the operating system to delete it (exit).
>Output data from child to parent (via wait).
>Process’ resources are deallocated by operating system.
>Parent may terminate execution of children processes (abort).
>Child has exceeded allocated resources.
>Task assigned to child is no longer required.
>Parent is exiting.
>Operating system does not allow child to continue if its parent terminates.
>Cascading termination.
>In Unix, if parent exits children are assigned init as parent