reasons for and against meta-refresh in the context of a login page
<p>within my login code (index.php) there is a section for facebook login. it checks whether or not the user has been logged in. now i can't use headers to redirect the user to a different page because it produces the error</p>

<blockquote>
<pre><code>Warning: Cannot modify header information - headers already sent by
</code></pre>
  
  <p>(output started at
  C:\xampp\htdocs\kite\index.php:81) in
  C:\xampp\htdocs\kite\index.php on line
  196</p>
</blockquote>

<p>so as a result i've resorted to using to meta-refresh</p>

<pre><code>    &lt;?php 
                //if user is logged in already
                if ($user): ?&gt;
                &lt;?php 
                //redirect them to the user sonline page
echo '&lt;META HTTP-EQUIV="Refresh" Content="1; URL=main.php"&gt;'; 
                //if user is not logged in
                else: ?&gt;
                &lt;input name="fblogin" type="button" value="Login with Facebook" class="fblogin" onclick="location.href='&lt;?php echo $loginUrl; ?&gt;'"/&gt;
                &lt;?php endif ?&gt;
</code></pre>

<p>what are the advantages and disadvantages of this method?</p>

<p>thanking you in advance</p>

<hr>

<p>all i have on line 81 is</p>

<pre><code>&lt;?php // include the hashing class  
require ("resources/phpass/PasswordHash.php"); 
</code></pre>
