.htaccess help, replacing URI segment

I have a URL that looks like this...

http://www.domain/a/var

I am hoping it would be possible to rewrite the URL using .htaccess so that /a/ would be replaced by /b/.

Is开发者_如何学编程 that possible, and if so, how?

RewriteEngine On

RewriteRule ^a/(.*) /b/$1

This should do that you need

RewriteEngine on
RewriteRule ^/a/(.*) /b/$1

Note: You'll need to add [PT] or similar if you need mod_alias or mod_index or similar to work using the new path.