ackol's Den

Great cheatsheet for .htaccess with a good range of examples for most needs:http://www.thejackol.com/htaccess-cheatsheet/

Apache

Official documentation here: http://httpd.apache.org/docs/2.0/howto/htaccess.html

Mod_Rewrite Rules

Official documentation: http://httpd.apache.org/docs/2.0/misc/rewriteguide.html

Miscellaneous Helpful Links:

http://www.htaccess-guide.com/
http://www.javascriptkit.com/howto/htaccess.shtml http://www.htaccesseditor.com/en.shtml

Redirect All Links to WWW

Some site owners are concerned that users should always be redirected from sitename.com to www.sitename.com, or from mainsitename.com/addon to sitename.com. This can affect cookies, etc. IBBoard solved this issue with some .htaccess lines.

RewriteEngine on
RewriteCond %{HTTP_HOST} !^www.ibboard.co.uk$
RewriteCond %{THE_REQUEST} !^[^\]+\ /foldername(\?.*)?\ .*$
RewriteRule ^(.*)$ http://www.ibboard.co.uk/$1 [R=301,L]

RewriteCond %{HTTP_HOST} !^www.ibboard.co.uk$
RewriteRule ^$ http://www.ibboard.co.uk/ [R=301,L]

Pseudo-description

Check that the host doesn't match and check that the request isn't just the current folder without a trailing slash (or the current folder without a trailing slash with a query string) and then do a rewrite rule on that. The next rule then catches the host not maching but the request being /ibboard (i.e. some accessing www.hwtskins.co.uk/ibboard and not www.hwtskins.co.uk/ibboard/). Both rules then rewrite the request to use the required domain.

The two rules are required as a single rule with only the %{HTTP_HOST} condition causes requests to "http://www.hwtskins.co.uk/ibboard" to be incorrectly rewritten to "http://www.ibboard.co.uk//home/username/public_html/ibboard".