How child process still running when i exit terminal window?

Question

When I execute

dd if=/dev/zero of=/dev/null

Then close terminal window i see that dd still running and it's PPID is difference than first time. What is happening for dd process ?

whenever killing parent process kill the child process?

Answer 1

Closing an interactive non-login terminal (such as a terminal window in Gnome or kde) won't send a SIGHUP signal. You can change that behavior in other type of shell (via a huponexit option) but not in interactive non-login term's. See https://askubuntu.com/a/685291/798765 for more details on huponexit ;)