limit_req_zone: How to apply only to some requests containing some string in the URL?

[Brian08275660]

I read some information about REGEX and think I found the way to express "X
or x, preceded with something before": 

~*(.*)X

I think that the first two characters mean "match anycase", then the "(.*)"
would mean "any quantity of characters" and the "X" would mean that specific
letter.

Am I right?

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,244015,244136#msg-244136