Subdomain redirect to URL Parameter while keeping other url params intact
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I've looked like crazy for an answer to this - and I haven't been able to find one as of yet. My apologies in advance if I've missed something.

I'm looking to convert a subdomain to a url parameter while maintaining the other url pieces.

Such as:

http://sub.domain.tv/value redirects to http://domain.tv/value?campus=sub

This is what I've tried after looking through numerous posts on here:

    # campus
    RewriteCond %{HTTP_HOST} ^sub.domain.tv$ [NC]
    RewriteRule ^(.*)$ http://domain.tv/$1/?campus=sub [R=301,L]
which worked fine for redirecting sub.domain.tv to domain.tv?campus=sub, but does not work with the rest of the URL parameters (so heading to sub.domain.tv/value does nothing).

I've tried other examples with the %1 and $1 being used as variables, such as with this post:
http://stackoverflow.com/questions/1133106/htaccess-subdomain-redirct-with-last-url-parameter but I don't understand the difference (and the examples I've tried did not work).

Thanks for taking a look! :) I very much appreciate it!
