PHP same page echoing (using die funct.)
<pre><code>    &lt;?php                    //filename signup.php
    ob_start();
 include('dat.php');
    if (!empty($_POST)){


        if ($pass!="d41d8cd98f00b204e9800998ecf8427e" OR $user!="") {       // 1
            $result=mysql_query($sql);
            if(mysql_error()) {
                die('Sorry, this username already exists');                 // 2
            }
        } else {
        echo "Please enter the Password";
        }
    }

    ob_end_flush();
    ?&gt;

&lt;html&gt;
&lt;body&gt;
&lt;form name="form1" method="post" action="signup.php"&gt;                &lt;!--3--&gt;
Username&lt;input name="myusername" type="text" id="myusername" /&gt;
Password&lt;input name="mypassword" type="text" id="mypassword" /&gt;
e-mail&lt;input name="email" type="text" id="email" /&gt;
&lt;input type="submit" name="Submit" value="Login" /&gt;
&lt;/form&gt;
&lt;/body&gt;
&lt;/html&gt;
</code></pre>

<p>This is a sign up page (All the mysql details are missing here, they are included in dat.php) . If there is ny error , it is displayed in the same page.<br>
problem 1 : [ //1 ] what is the operator for OR , in this case I have used the condition for if the pass or user is blank,but the OR is not working neither || , used in javascript.<br>
problem 2 : [ //2 ] if die is used , then the statement is printed in the new window , but I want it to appear in the same window...I also used echo, it worked but I feel like i am missing the main function of 'die' by using 'echo'.<br>
problem 3 : [ <code>&lt;!--3--&gt;</code> ] how can I replace signup.php as action to something like SERVER_PAGE or whatever...  </p>
