What is PID Unix? In computing, the process identifier (a.k.a. process ID or PID) is a number used by most operating system kernels—such as those of Unix, macOS and Windows—to uniquely identify an active process.
Is init a user process? Init is a user process like any other processes, so it is using virtual memory. The only thing that is special about init is that it is one of the two processes that the kernel started initially. When init is started by the kernel, it goes into user mode.
What is daemon in Linux? In Unix and Linux, a daemon is a program that runs in the background without requiring any user interaction. The file name of a software daemon usually ends in the letter d.
What is job control in Linux? Job control refers to the ability to selectively stop (suspend) the execution of processes and continue (resume) their execution at a later point. A user typically employs this facility via an interactive interface supplied jointly by the operating system kernel’s terminal driver and Bash.