- if the leader exits, and goes zombie, then several files under
"/proc/<pid>" won't work, though using "/proc/<pid>/task/<tid>"
would.
The latter path form is also generally better for being robust in
the case TID exits and is reused in another process, much like
tkill vs tgkill.
The part about TID-reuse robustness actually doesn't make sense here
yet, though, since this patch is not switching to
"/proc/<pid>/task/<tid>".
So reduce that to:
- if the leader (<pid>) had exited and is thus now zombie, then several
files under "/proc/<pid>" won't work, while they will if you use
"/proc/<lwp>".
Otherwise LGTM.