[Resolved, thanks] Query Strings in URL

[eluser]Fenix[/eluser]
Is there any way to use query strings for only part of a URL (and only for one controller)? I am making a REST API for a site and the following example would be ideal:

Controller: api
Method: categories

http://mysite.com/api/categories?count=0...ingapi.com

[eluser]sharpe[/eluser]
try this

function categories()
{
$this->config->set_item('uri_protocol','PATH_INFO');
parse_str($_SERVER['QUERY_STRING'],$_GET);
print_r($_GET);
//bla bla
}

[eluser]Fenix[/eluser]
could you give an example of the output for that please? i don't have any code written yet and thought i better get this figured out before i begin.

[eluser]Fenix[/eluser]
Nevermind, I tried it and got errors.

http://mysite.com/api/categories?count=0...1175756400

A PHP Error was encountered
Severity: Notice
Message: Use of undefined constant Ôuri_protocolÕ - assumed 'Ôuri_protocolÕ'
Filename: controllers/api.php
Line Number: 17

A PHP Error was encountered
Severity: Notice
Message: Use of undefined constant ÔPATH_INFOÕ - assumed 'ÔPATH_INFOÕ'
Filename: controllers/api.php
Line Number: 17

A PHP Error was encountered
Severity: Notice
Message: Use of undefined constant ÔQUERY_STRINGÕ - assumed 'ÔQUERY_STRINGÕ'
Filename: controllers/api.php
Line Number: 18

A PHP Error was encountered
Severity: Notice
Message: Undefined index: ÔQUERY_STRINGÕ
Filename: controllers/api.php
Line Number: 18

[eluser]pistolPete[/eluser]
You should not copy directly from above:
The forum software converted the quotes because the code was not posted in [ code ] tags

Code:

parse_str($_SERVER['QUERY_STRING'],$_GET);
print_r($_GET);

[eluser]Fenix[/eluser]
Ok thanks, I didn't even notice.

It works without this line, which is fine because I'm not even sure what it does because it wasn't explained.

Code:

$this->config->set_item(‘uri_protocol’,‘PATH_INFO’);

Thanks

[eluser]jabberjab[/eluser]
I've been trying to follow what has been written here but I am unable to use query strings on this example URL.

Code:

example.com/user/add?title=someTitle&url=http://someurl.com

I have however been able to use query strings on

Code:

example.com/index.php?c=user&m=add&title=someTitle&url=http://someurl.com

Anyone got a suggestion as to how to achieve the first type of URL? I am guessing I should probably route it somehow. It'd be great if someone could let me know or at least point me in the right direction Thanks.

Also: So that there's no misunderstanding. I'm using .htaccess to remove the need of index.php, which is why I'd definitely like the solution presented in the first URL