subdomain error redirect

[inotgood]

Can somebody give me a htaccess code that redirect user to a specified page if subdomain or page does not exist from if the .htaccess file is on the top level domain folder.

for example:

.htaccess file is inside htdocs folder (which is www.domain.com/.htaccess)

whats the code for the file at that location to redirect a non-existent subdoman or page to a specified page

[NogDog]

ErrorDocument 404 http://www.example.com/error_pages/error404.php

[inotgood]

NogDog wrote:

ErrorDocument 404 http://www.example.com/error_pages/error404.php

that will only work for the top level domain, im talking the subdomain

the .htaccess is at http://domain.com/.htaccess

whats the code for the .htaccess file at the tld place that can redirect a non-existent subdomain or page on the subdomain of the domain

for example the if the index page of the sub.domain.com is a 404
is there a code for the .htaccess file at the top level domain root to redirect it?

[NogDog]

I don't think it's possible for a non-existent sub-domain, as the request will never get far enough to actually read any .htaccess files: you'll just get a "server not found" error on the browser.