The most straightforward way would be to create an open filehandle in exclusive mode and retry with another name if that fails. You can't get it to work correctly testing on filenames directly - unless you implement a separate locking mechanism that'll probably just complicate matters.

See sysopen and perlopentut. Also File::Temp for an implementation of that idea.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: CGI filename race by Joost
in thread CGI filename race by songahji

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