Basically I want to set up a simple session that will tell me what the last page someone was on was (so like $_SESSION['lastpage']="home"; would be on the homepage, or whatever).

Only for some reason the system (something I am fixing up that someone else has written) doesn't want to play ball. They use sessions and they seem to work fine, however any that I try and call myself just don't work.

Here is sessions.php which gets called on every page that uses sessions, but I don't see how this could effect what I am trying to do.

PHP Code:

<?php 
require_once("dbfactory.php");
define("STAMP_FORM", "YmdHis"); // Default timestamp format.

function sess_connectDB(){
    /*
        function to connect to the backend database with local db defined parameters.
    */
    try  {
        $dbh = new DBFactory(); 
        return $dbh;
    }
    catch(ADODB_Exception $e){
        header("Location: nodb.php");
        exit;
    }
}
function sopen($save_path, $session_name){    
    /*
        No need to do anything here.
    */
    return true;
}
function sclose(){
    /*
        No need to do anything here.
    */
    return true;
}
function sread($id){
    /*
        Reads session data from the database
    */
    $dbh = sess_connectDB();
    $sql = "SELECT * FROM `TS::Sessions` WHERE sid='$id'";
    $dbh->SetFetchMode("ASSOC");
    $rs = $dbh->Execute($sql);
    $row = $rs[0];//->fields;    
    //print_r($row);
    return $row['sdata'];
}
function swrite($id, $sess_data) {
    /*
        Writes session data to the database
    */
    try {
        $dbh = sess_connectDB();
        $clean_data = $dbh->qstr($sess_data);
        $timestamp = date(STAMP_FORM);
        $sql = "DELETE FROM `TS::Sessions` WHERE sid='$id'";
        $dbh->Execute($sql);
        $sql = "INSERT INTO `TS::Sessions` (sid, sdata, modtime) VALUES('$id', $clean_data, '$timestamp')";
        $dbh->Execute($sql);
        //printr($sql);
    }
    catch (Exception $e){
        var_dump($e);
    }
}
function sdestroy($id){
    /*
        We are finished with the db, so wipe the session
    */
    $dbh = sess_connectDB();
    $dbh->Execute("DELETE FROM `TS::Sessions` WHERE sid='$id'");
    $_SESSION= array();
}
function s_gc($maxlifetime){
    /*
        Garbaage collection.
    */
    $dbh = sess_connectDB();
    $ts = time() - $maxlifetime;
    $timestamp = date(STAMP_FORM, $ts);
    $dbh->Execute("DELETE FROM `TS::Sessions` WHERE modtime < '$timestamp'");
}

// Make PHP use *our* session handling.
if (session_set_save_handler( 
  "sopen", 
  "sclose", 
  "sread", 
  "swrite", 
  "sdestroy", 
  "s_gc" 
)===false){
    die("Sessions are broken");
}

// As this will be included in any page that wants session access, we might as well start it here.
session_start();

Any suggestions?

On many servers, session_start() belongs at the very top of the page, in fact it won't work if it isn't the very first line, and isn't on a line by itself, with not even a space after the semi-colon.

But besides that, all I see you doing is stuff with the database. Shouldn't you just be using the $_SESSION[] superglobal, as your title seems to indicate? As far as I am aware, session_start() is only used when you need access to it.

Cheers for the advice, I have got it sorted, I needed to include the sessions.php file in the tester.php - I didn't think this was necessary because of the global nature of sessions. Oh well! Cheers everyone.

Originally Posted by wayfarer07

On many servers, session_start() belongs at the very top of the page, in fact it won't work if it isn't the very first line, and isn't on a line by itself, with not even a space after the semi-colon.

What??? The only requirement for session_start() is that it be called BEFORE any output is sent through the buffer. It would be impossible for modern apps to have sessions start the very first line because scripts require to include function and class files first, and in some cases a connection to the DB.

What???

Maybe it is not as widespread as I suggested. However, I have encountered this problem, and the only thing I could do on this one server, was to place the session_start() on a line by itself, before any other code, and A SINGLE SPACE after the semi-colon would mess up all my sessions. I wouldn't be saying this if I hadn't witnessed it with my own eyes, because I know, it makes zero sense. Since then, it has never happened to me, but I live in fear of it, I suppose, because it did happen. Has this ever happened to anyone else?