We've got a total misunderstanding... what you said has nothing to do with my question. I'm sorry I wasn't very clear.
Take an old classic generic WordPress theme. I have multiple blogs using that theme. On the front page of my blog I want to put an introductory paragraph of text below the header but before the loop through the most recent posts. So I called up that theme's index.php at the following location I want to insert some code...
//I want to put some conditional code right here!
<?php if (have_posts()) : while (have_posts()) : the_post(); ?>
That conditional code is based on which blog it is. I've been told there's some sort of global variable such as $blog_id that is unique to each blog in my installation.
What I want to know is is there such a variable available? Is there a "get_blog_id()" function somewhere?
Let me put the question a different way. Help me write a piece of code that tells me what my blog ID number is such as this...
<p>The unique ID number of this blog is: <?php echo get_blog_id(); ?></p>
Except that doesn't work as there is no such function. What do I do instead? Moreover if it is a variable and not a function point me to a place in the codex or somewhere that lists all such variables available.