.htaccess - htaccess 子域 id 类别

Question

plz我想用htaccess将类别更改为子域：例如这是我的网址

http://my-url.com/index.php?id_cat=29&l=category-name-here

我想将其重写为：

http://category-name-here.my-url.com

   and this is what i try but i cant find what i want 

        Options +FollowSymLinks
    RewriteBase /

    RewriteCond %{HTTP_HOST} !^www.your-domain-name.com [NC]
    RewriteCond %{HTTP_HOST} ^(www.)?([^.]+).your-domain-name.com$ [NC]
    RewriteRule ^([^.]+)$ /some_file.php/$1?subdomain=%2 [L,QSA]


thank you