Mastering nohup: Running Unix Processes Without Hangups
Introduction When you log into a Unix or Linux system over SSH, you’re essentially opening a session that is bound to a controlling terminal. As long as that terminal exists, the kernel delivers signals—most notably SIGHUP (hang‑up)—to every process that belongs to the session. If the terminal disappears (for example, you close your SSH client or lose network connectivity), the kernel sends SIGHUP to the foreground and background jobs, and many of those jobs terminate by default. ...