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From: Lew Pitcher <lew.pitcher@digitalfreehold.ca>
Newsgroups: comp.unix.programmer
Subject: Re: Why does getppid() still return old parent pid after setsid()?
Date: Mon, 11 Nov 2024 17:08:20 -0000 (UTC)
Organization: A noiseless patient Spider
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On Sat, 09 Nov 2024 09:25:22 +0000, Kenny McCormack wrote:
[snip]
>  As
> far as I know, in classic Unix, the only way for a process to get
> "re-parented" is to have the parent die.  Of course, as others have noted,
> under Linux, there is also the re-parenting "prctl".

Kenny, could you elaborate on the use of prctl() to "reparent" a process?
I've not seen examples of how to do this, and the prctl(2) manpage doesn't
explicitly indicate the options necessary.

I don't see any option that controls or modifies a process PPID. The only
prctl(2) options that I can see relating to "reparenting" are the
PR_SET_CHILD_SUBREAPER and PR_GET_CHILD_SUBREAPER options that
seem to govern who gets SIGCHLD on the child's death. Is this what you
mean by "reparenting"? 

[snip]


-- 
Lew Pitcher
"In Skills We Trust"