37.1. Overview

A daemon is a process with the following characteristics:

• It is long-lived. Often, a daemon is created at system startup and runs until the system is shut down.

• It runs in the background and has no controlling terminal. The lack of a controlling terminal ensures that the kernel never automatically generates any job-control or terminal-related signals (such as SIGINT, SIGTSTP, and SIGHUP) for a daemon.