Change Wordpress feed <link> for one specific tag -

i have external page reads rss feed tag. can't change on external page, challenge change rss feed on side match requirements. on external page 3 latest posts tag shown, , @ end of section (note: not after each post after 3 posts) there "view all" link. link receives value element in feed, default set blog homepage, e.g. http://myblog.com). specific tag link should http://myblog.com/tag/myspecialtag.

the requirement "view all" link links tag page instead of homepage.

my idea add condition element change url specific category. tried change feed template recommended here: customizing feeds, reason doesn't change template @ all. code tried following:

remove_all_actions( 'do_feed_rss2' ); add_action( 'do_feed_rss2', 'change_feed_rss2', 10, 1 );  function change_feed_rss2( $for_comments ) {     $rss_template = get_template_directory() . '/feeds/feed-custom_rss2.php';     if( file_exists( $rss_template ) )         load_template( $rss_template );     else         do_feed_rss2( $for_comments ); // call default function } 

of course created custom feed template , stored in feeds directory in theme.

as didn't work tried looking filters/hooks couldn't find helpful regarding issue. ideas on how best solve issue?

i came following solution: created new custom page template custom_rss-feed.php , copied code wp-includes/feed-rss.php it. assigned template new page. additionally added filter get_bloginfo_rss following:

function alter_bloginfo_rss($value, $key) {      if ( $key === "url" &&         is_page_template("custom_rss-feed.php")     ) {          return $value . "/my/custom/url";     }      return $value; }  add_filter("get_bloginfo_rss", "alter_bloginfo_rss", 10, 2);