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From Jim Jagielski <...@jaguNET.com>
Subject Re: SYSV Semaphores.
Date Mon, 11 Dec 2000 14:46:22 GMT
Bill Stoddard wrote:
> 
> 
> > Another issue, IIRC, was the fact that with semaphores, you can't
> > ensure that they are cleaned up and deleted if a process crashes,
> > as you can with SysV shared mem. In fact, this may have been at
> > the heart of the DoS attack.
> >
> > --
> > ===========================================================================
> >    Jim Jagielski   [|]   jim@jaguNET.com   [|]   http://www.jaguNET.com/
> 
> >From what I have read (and my meager understanding of Unix kernels), I think
> you would leak resources only if the parent process crashed (or was
> kill'ed -9).
> 

yeah, mostly. It's just that you can't "pre-delete" a sem like
you can a SysV shared memory segment... so if whatever process
dies that's supposed to semctl(...IPC_RMID...) then we'll leak.

-- 
===========================================================================
   Jim Jagielski   [|]   jim@jaguNET.com   [|]   http://www.jaguNET.com/
          "Casanova will have many weapons; To beat him you will
              have to have more than forks and flatulence."

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