I keep coming back to my first thought, which I dismiss as "that's too easy." But since it keeps entering my mind I'll mention it:

What if you have two instances of the script itself on your filesystem? Is it possible that your cron invokes a script at one path, and your testing invokes a script in ~/bin/ for example? They would be separate files, so totally different locks.

I did toy with the relative path consideration, but could never reproduce a situation where invocations from different working directories (hence, different relative paths, but the same absolute path) would result in different locks. If there's only one file that you're running, it's going to be the same thing being locked.


Dave

In reply to Re: singleton lock not reliable by davido
in thread singleton lock not reliable by pidloop

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