You forgot to escape your dot. It will match any character, not just a dot.

Furthermore, some files have dots, but no extentions. For example, consider "Foo. Bar". ". Bar" is not an extention because it has a space in it. You can verify this by checking the properties of "Foo. Bar" and "Foo.Bar". For the former, the file type is "File", while for the latter, the file type in "BAR File". You (and everyone in this thread) mistakenly identify ". Bar" as an extention and don't convert "Foo. Bar" to "Foo_ Bar".

The correct usage would be:
fileparse($_, qr/\.[^. ]*/)

In reply to Re: AWTDI: Renaming files using regexp by ikegami
in thread AWTDI: Renaming files using regexp by nimdokk

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