How to pass a variable $ _ GET in a page? I will wish to create a privileged space for some users.

I create a role 'Candidate'. I assigned permission 'access user profiles' has this role.
I create a user that uses this role. (eg, foo)

Secondly, I create a menu (see below)

$items['candidate/%candidate'] = array(
  'title'            =&gt; t('My candidate space'),
  'description'      =&gt; '',
  'page callback'    =&gt; 'cel_configuration_custom_page',
  'page arguments'   =&gt; array(1),
  'access arguments' =&gt; array('access user profiles'),
  'access callback' =&gt; TRUE,
);


Then a linked function

function cel_configuration_custom_page($args){
  return 'custom';
}


Finally, I have emptied the cache.

When I go on the candidate/1 page with my account 'toto' or account 'admin', I have not found page.

Why?
Try the following code:

    $items['candidate/%user'] = array(
      'title'            =&gt; t('My candidate space'),
      'page callback'    =&gt; 'cel_configuration_custom_page',
      'page arguments'   =&gt; array(1),
      'access arguments' =&gt; array('access user profiles'),
    );

    function cel_configuration_custom_page($account){
      return 'Custom page for ' . $account-&gt;name;
    }


You can't use %candidate as an argument for user accounts. Also, if you want to restrict access by a particular permission, don't set access callback to TRUE as that will grant access to everyone.