On Thu, Apr 04, 2019 at 03:54:50PM +0200, Christian Brauner wrote:
> Hey Michael,
>
> While working on pidfd Jann and I realized that TIDs don't get listed in
>
> ls -al /proc
>
> which is intended behavior. However, the directories for them still
> exist i.e.
>
> ls -al /proc/<tid>
>
> works perfectly fine and so by extension do things like
>
> cat /proc/<tid>/status.
>
> This is information was new to us, as it was for some other people as
> well. Afaict, the manpage for procfs doesn't mention this behavior at
> all. I think it really should as this quite some implications:
> - threads can be accessed via open("/proc/<tid>", ...) just as
> thread-group leaders can
> - all files that are available for thread-group leaders are available
> for threads as well (This is not the case when going through
> /proc/<pid>/task/<tid>.)
> (Implementation-wise this means that threads are available once as
> through tgid_proc_operations and once through tid_proc_operations but
> that detail probably doesn't need to show up in the manpage.)
>
> This is apparently part of the API so we should really document it. :)
Well, apparently you already did and it's just that even on Disco Dingo
the manpages are not new enough or a new version with this hasn't been
released. Sorry for the noise!
Christian
