5 x Re: how to make a demon in perl?

I can see what is happening I am just having trouble understanding why it works

I figured the order was important. I thought if the child inherited normal STDIN etc then redirected them it would be the same as running a normal script and trying to detach by redirecting STDIN etc (see 1). The child wouldn't be detached and would die on SIGHUP or whatever.

I might just have to accept that I see it but don't fully understand it. Thanks for your posts though!

(1) I have tried the daemon script without fork and it doesn't work since just doing the redirecting of file descriptors of a process doesn't seem to detach.

--blm--

Comment on 5 x Re: how to make a demon in perl?

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Re: 5 x Re: how to make a demon in perl? by zigdon (Deacon) on Oct 01, 2002 at 14:15 UTC
Ok - I think I see your confusion. As far as I know, there is no connection between file descriptiors and signals. Meaning, the fact that you close redirect your STDIN/STDERR in your script doesn't stop the shell from sending you a SIGHUP when the parent exits. You have to disassociate yourself from your parent process, which is what the setsid call does (I think). -- Dan	[reply]