session start has been evoked.
I need the value of $v.

     $key   = $_SESSION['sys_var_key'];
     $v     = $_SESSION[$key];

echo '<br>key  =>'.$key;
echo '<br>value  =>'.$v;

From the discussion, your question is not all that clear. But if you want the value of $v, I'm afraid you are already having it when you used

echo '<br>value  =>'.$v;

So if you want something else, can you kindly elucidate your question.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.