SPUG: tracking PIDs

[Andrew Sweger]

On Mon, 26 Aug 2002, Jonathan Gardner wrote:

> There is a small chance that the child has been long dead and you have cycled 
> through the available PIDs, and a different process is running as that PID, 
> but what can you do about that?

If a somewhat unique value (other than a PID) is included in the command
line of each process spawned in this particular system, this value's
existence can be checked in /proc/$pid/cmdline on systems that support
procfs. So, along with tracking PIDs, these unique values would also need
to be tracked. If the PID is still alive (via the kill 0 test), check the
cmdline to see if it still matches the previously recorded signature.

-- 
Andrew B. Sweger -- The great thing about multitasking is that several
                                things can go wrong at once.


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