FAQ 8.36 How do I fork a daemon process?

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8.36: How do I fork a daemon process?

If by daemon process you mean one that's detached (disassociated from
its tty), then the following process is reported to work on most Unixish
systems. Non-Unix users should check their Your_OS::Process module for
other solutions.

* Open /dev/tty and use the TIOCNOTTY ioctl on it. See tty for
details. Or better yet, you can just use the POSIX::setsid()
function, so you don't have to worry about process groups.

* Change directory to /

* Reopen STDIN, STDOUT, and STDERR so they're not connected to the old
tty.

* Background yourself like this:

fork && exit;

The Proc::Daemon module, available from CPAN, provides a function to
perform these actions for you.



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