How are PID's generated?

Posted by Helltone on Super User See other posts from Super User or by Helltone
Published on 2010-04-26T14:08:59Z Indexed on 2010/04/27 0:14 UTC
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unix

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process-id

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algorithm

On *nix, PIDs are unique identifiers for running processes. How are PID's generated? Is it just an integer which gets incremented or a more complex structure such as a list? How do they get recycled? By recycling I mean that, when a process terminates, it's PID will eventually be reused by another process.

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