mod_rewrite to remove index.php from Codeigniter in subdirectory - apache

Question

Codeigniter applications commonly use mod_rewrite to exclude the string index.php from the url. I have two Codeigniter applications within the same domain. One Codigniter application is in the web root folder, another Codigniter application is in a subfolder of the web root folder.
Codeigniter application 1:
http://domain.com/index.php
Codeigniter application 2 (the landing page application):
http://domain.com/land/index.php
The two Codeigniter applications are each atomic and do not share any files between them. Every file in the Codeigniter framework is in public_html/ and again in public_html/land/. So I need to exclude the string index.php in urls addressing the root / folder and also exclude the string index.php in the /land/ subfolder.
The .htaccess file in the root folder uses the widely recommended mod_rewrite rules (code below) from the Codeigniter wiki, and this set of rules works well for the root Codeigniter application (application 1). These rules reside in web root folder.
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
#Removes access to the system folder by users.
#Additionally this will allow you to create a System.php controller,
#previously this would not have been possible.
#'system' can be replaced if you have renamed your system folder.
RewriteCond %{REQUEST_URI} ^system.*
RewriteRule ^(.*)$ /index.php?/$1 [L]
#When your application folder isn't in the system folder
#This snippet prevents user access to the application folder
#Rename 'application' to your applications folder name.
RewriteCond %{REQUEST_URI} ^application.*
RewriteRule ^(.*)$ /index.php?/$1 [L]
#Checks to see if the user is attempting to access a valid file,
#such as an image or css document, if this isn't true it sends the
#request to index.php
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?/$1 [L]
</IfModule>
<IfModule !mod_rewrite.c>
# If we don't have mod_rewrite installed, all 404's
# can be sent to index.php, and everything works as normal.
ErrorDocument 404 /index.php
</IfModule>
The above set of rules has no problem removing index.php from the urls in the root Codeigniter application. But this set of rules does not seem to allow the mod_rewrite rules in public_html/land/.htaccess to execute.
When I remove the mod_rewrite rules in public_html/.htaccess, then the mod_rewrite rules in public_html/land/.htaccess start being evaluated.
Is there a way to change the mod_rewrite rules in public_html/.htaccess to handle the special case of a url intended to access the /land/ subfolder?
I think the best solution might be to change the mod_rewrite rules in public_html/.htaccess to allow the mod_rewrite rules in public_html/land/.htaccess to execute when the subfolder is addressed in the url. I am open to any suggestions.
Pre-emptive answer to the question "why don't you just use a subdomain?" 1. Saving money on the SSL certificate. 2) Non-techical users are sometimes confused by subdomains for marketing the base domain name.
Pre-emptive answer to "why don't you combine the Codeigniter applications to use the same files in the framework?" Duplicating the framework files is an easy way to keep the versioning repositories separated.

Answer 1

The problem is the rules in public_html/.htaccess are rewriting the URL's going to /land/, you need a passthrough which makes it so nothing happens when /land/ is requested.Add:
RewriteRule ^land/ - [L]
before the rest of your rules.

Answer 2

Add a rule at the top to just go to the land subfolder if it's part of the request string. That way, the rules in /land/.htaccess will be executed instead of the subsequent rules in /.htaccess. So put this at the top:
RewriteRule ^land.*$ - [NC,L]
This will check if the request begins with 'land' and redirect it to the subdirectory, where .htaccess rules corresponding to that subdirectory will be applied instead.
The reason the existing rule checking for files and folders and not doing the rewrite if the request corresponds to one of them is because whatever follows 'land' in the request is probably not a real file, and so the rewrite rule fires.