I understand. And I think it is a good thing to check if the filenames are supplied by (especially novice) users.

If they enter a filename "temp\fred.txt", you could end creating fred.txt in the temp subdirectory rather than their expectation on a file called temp\fred.txt in \.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re^6: Regular expression to check for invalid file name characters by BrowserUk
in thread Regular expression to check for invalid file name characters by merrymonk

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