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From: Pedro Alves <pedro@codesourcery.com>
Organization: CodeSourcery
To: Pavel Emelyanov <xemul@parallels.com>
Subject: Re: [rfc 2/3] fs, proc: Introduce the Children: line in /proc/<pid>/status
Date: Fri, 2 Dec 2011 12:58:03 +0000
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Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
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On Friday 02 December 2011 12:43:10, Pavel Emelyanov wrote:

> >> Yes, I like /children file. other points seems to be pointed out by other
> >> reviewers. 
> > 
> > Any reason this is a file instead of a directory like /proc/PID/task/ ?
> > 
> > $ sudo ls /proc/8167/task/
> > 8167  854  855  856  857  858  859
> > $ sudo ls /proc/8167/task/855/
> > attr    clear_refs  cpuset   exe     io       loginuid  mountinfo  oom_adj        pagemap      sched      smaps  statm    wchan
> > auxv    cmdline     cwd      fd      latency  maps      mounts     oom_score      personality  schedstat  stack  status
> > cgroup  comm        environ  fdinfo  limits   mem       numa_maps  oom_score_adj  root         sessionid  stat   syscall
> > 
> > Much easier to follow the chain from the command line this way.
> 
> What do you propose to put into these directories? Another directories named with
> children pid-s?

Yes, just like the task/ dir gives you directories named with the
processes's thread ids.  Opening /proc/PID/children/PID-CHILD1/ would get
you the same as opening /proc/PID-CHILD1/.  Just like
opening /proc/PID/task/PID-CHILD1/ gets you (almost) the same as opening
/proc/PID-CHILD1/.

-- 
Pedro Alves