Another idea is specify only allowed characters, like ascii letters and numbers dash and underscore

s![^abcdefghijklmnopqrstuvwxyz0123456789_\-]!!gi
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or create sha1 hash of the file and use that as the filename

$ perl -MDigest -le "  $sha256 = Digest->new(q!SHA-256!); $sha256->add
+file( *STDIN ); print $sha256->hexdigest " < test
a505e6720df306ab46a6b24c458b8b77b60bffa18d831f4796ba1b736bb44c6c
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