How does nohup work?

Question

What happens behind the scenes when a program runs without nohup?

Is the PID of the parent process changed?

Thank.

EDIT : I realized that nohup (and disable) causes SIGHUP to not be sent to the process if the parent process receives it. Does this mean that this is equivalent to processing SIGHUP (and actually ignoring it)?

Answer 1

Use the source, Luke!

Answer 2

This is equivalent to setting the handler SIGHUPto SIG_IGN, i.e.

signal(SIGHUP, SIG_IGN);

Answer 3

nohup .