Operating in Process

• Process 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.

• 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.