Do you mean by two instances of the same script both calling localtime at the same second?

Exactly. IIRC the discussion was about a CGI. As ling as there is just one user - No Problem. But as soon as there is more than one chances are good that 2 users will click the button at the same time.

However. Neither of our solutions is a perfect solution. Just ideas.

If I had to calculate a new unique filename, I would still use $$ append a counter until I find a unique one. Additionally I would set a lock before searching for a free name.

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

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