How to add extra menu source and access it in a theme

Question

The Menu module contains 2 sources to assign menus to my site.

How do I add a 3rd source?

Reading through the Zen theme code, I see the variables $main_menu, and $secondary_menu.

I would like to access this 3rd menu source through a variable called $global_menu.

How do I set this variable from a module?

EDIT

I put this at the bottom of the zen_proprocess_page hook in template.php

$global_menu = menu_navigation_links('menu-global-menu');

and was able to access it with this in page.tpl.php so thank you for that advice

<?php if ($global_menu): ?>
   <div class="global-navigation">
      <ul class="nav">
      <?php foreach ($global_menu as $key => $value): ?>
        <li>
          <a href="<?php print($value["href"]); ?>" class="global-link" ><?php print($value["title"]); ?></a>              
        </li>
      <?php endforeach;  ?>
    </ul>
    </div>
 <?php endif; ?>

EDIT

Moved multipart question to new question

Answer 1

To be able to put it in a theme variable I think you're looking at something like the following. Please note I haven't tested this, but i should put you in the right direction.

In your template.php or a module:

function MYTHEME_preprocess_page($vars){
  $global_menu = menu_navigation_links('menu-global-menu');
  $vars['global_menu'] = theme('links__menu_global_menu', array('links' => $global_menu));
}

Then clear your theme registry/caches.

Answer 2

From what I understand you want a create a menu (called 'global menu') separate from the 'Main' and 'Secondary' menus,and you want to display that at a desired location in your theme.

The best way to do this is -

1. Create a new Menu from - YOURSITE/admin/structure/menu/add. Call it 'global menu'
2. Add links to it
3. Goto the blocks page and place the 'global menu' block (which is automatically generated for you after step #1) in the theme region of your choice - YOURSITE/admin/structure/block