Rewrite only a specific file using MOD_REWRITE

Question

I have a file that can be reached using multiple paths:

http://mydomain.com/portal1/movie.swf
http://mydomain.com/portal2/movie.swf
http://mydomain.com/portal1/substep/movie.swf
etc.

I want a rewrite rule to get this specific file from the following path:

http://mydomain.com/movie.swf

How can I do that?

Answer 1

in .htaccess in your main folder:

RewriteRule ^portal.*movie\.swf$ /movie.swf [L]

(backlash before the dot added after Gumbos comment. +1)