Operations on Processes

Just as living things do, processes also have life cycles and family relations. A running process can control other processes via process operations (or functions.) Each operation that we call upon a process will either change the phase in its life cycle or modify its family.

1. A running process can create (also: spawn or fork) a new process.
   • In such a case, the original process is called the parent process, and the created one is referred to as the child process.
   • Every created process will be given a unique ID. In addition, each process will also store its parent’s ID.
   • Well, if a process can create another process, who then is the first process that runs on the computer? This is usually the process scheduler program, and it is given the ID of 0.
   • The process scheduler then launches a process called init (or systemd in newer Linux versions) with the ID of 1. init then proceeds to create all the other processes on the computer, thereby becoming the Great Parent of all processes.