I also didn't say that it's guaranteed to give you a unique filename.

Nope, but the OP asked for that.

$$ is uniqe as long as the system is not rebooted and as long as there is no overflow in the machines process counter. It might happen, but it's not very probable

pids are assigned sequentially until a certain point (most probably 32767) is reached. Then they wrap around to 0. Rebooting also resets the count to 0. The chances of either reaching 32767 or a reboot are just about 100%, which is more probable than two instances of the same script calling localtime within the same second.Incidently, on AIX pids maybe reused within seconds.

But regarding localtime: it's almost sure that you will get the same result quite often

I'm not sure how? Do you mean by two instances of the same script both calling localtime at the same second?

In reply to Re: Re: Re: Re: Non-Duplicate File Names, Security, and Self Cleaning by bm
in thread Non-Duplicate File Names, Security, and Self Cleaning by Petras

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