Re: inotify back end for tail -f on linux

[Jim Meyering]

Giuseppe Scrivano wrote:
> Jim Meyering <address@hidden> writes:
>
>> Actually, there may be a nice way to allow --pid=PID to
>> integrate seamlessly with inotify support.
>>
>> I think you can add an IN_DELETE_SELF inotify watch on the "/proc/PID"
>> directory.  I suspect that every system with inotify support also
>> has usable /proc/PID directories.  The only requirement seems to be
>> that the desired directory be readable.
>
> I tried to watch /proc/$PID using inotify-tools and a few lines program
> that I wrote ad-hoc and it seems I can't monitor /proc correctly.
> I didn't receive IN_DELETE_SELF or any other message when the $PID
> process was killed.
>
> It seems I can't use inotify in this direct way to monitor processes
> status.

Rats.
After you mentioned that, I tried

  inotifywatch /proc/$pid
and
  inotifywatch /proc/$pid/mem

and confirmed your finding.  They don't work.
Then I read on lkml that it appears the linux kernel deliberately
does not enable inotify for /proc.