htaccess file help needed please

[deloreandude]

hi, im new to this forum, so hello everyone

 

ok down to business, i have had problems with my htaccess file. which consists of the following

 

RewriteCond %{HTTP_HOST} ^.*$

RewriteRule ^/?$

http://www.mydomain.com/subdir/

[R=301,L]

 

ok heres the problem, although the site works, when you hit www.mydomain.com you are redirected to the subdir folder where the site lives. Great... but.. its shows the address with the subdir in the address bar (never used too)

how can i stop this from happening..

 

what exactly is the 4 lines above doing..

 

and if anyone can help one last thing.. how can i make it so that if someone types

 

www.mydomain.com/forum  they are automatically redirected to  www.mydomain.com/subder/index.php?forum 

but again leaving forum in the address bar

 

any help would be greatly appreciated.. thanks a million..

 

deloreandude