How to disable valid_referers?

[Horus Lee]

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Hi guys,

Say if I have many files under / (document root), all of them need
hotlink protection, except one.

I set valid_referers for location / as default, how could I skip the
proection for the specific file?

I guess I can't simply put "valid_referers none" here according to the
documentation at http://wiki.nginx.org/HttpRefererModule (It says
default: none, but I guess this will confuse people with the value "none").

Any help will be greatly appreciated.
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