Q:

Redirect URL with mod_rewrite with variable

I am looking to get a rule setup to change one of my URL's. After much research I understand the basics of mod_rewrite. The trouble I am having is the dynamic URL that is being re written. I have outlined in as much detail possible the task and desired outcome. 
I currently have a url that looks like this:
http://www.myndness.com/my-canvas/{username}/

The {Username} is variable depending on which user you click on.
What I need to do is add /?my_posts to the end of that URL. This will then display the posts module by default for all users. 
So all the users will follow the same URL pattern:
/User1/?my_posts
/User2/?my_posts
/User3/?my_posts
/User4/?my_posts

Apologies if I have missed anything. 
I am using WordPress and have access to all files on the server.

A:

Try this:
RewriteEngine On
RewriteCond %{QUERY_STRING} ^$
RewriteRule ^my-canvas/[^/]+/?$ $0?my_posts [R=301,L,NC]

