How do I close a connection early?

by

The following PHP manual page (incl. user-notes) suggests multiple instructions on how to close the TCP connection to the browser without ending the PHP script:

Supposedly it requires a bit more than sending a close header.

OP then confirms: yup, this did the trick: pointing to user-note #71172 (Nov 2006) copied here:

Closing the users browser connection whilst keeping your php script running has been an issue since [PHP] 4.1, when the behaviour of register_shutdown_function() was modified so that it would not automatically close the users connection.

sts at mail dot xubion dot hu Posted the original solution:

<?php
header("Connection: close");
ob_start();
phpinfo();
$size = ob_get_length();
header("Content-Length: $size");
ob_end_flush();
flush();
sleep(13);
error_log("do something in the background");
?>

Which works fine until you substitute phpinfo() for echo('text I want user to see'); in which case the headers are never sent!

The solution is to explicitly turn off output buffering and clear the buffer prior to sending your header information. Example:

<?php
ob_end_clean();
header("Connection: close");
ignore_user_abort(true); // just to be safe
ob_start();
echo('Text the user will see');
$size = ob_get_length();
header("Content-Length: $size");
ob_end_flush(); // Strange behaviour, will not work
flush(); // Unless both are called !
// Do processing here 
sleep(30);
echo('Text user will never see');
?>

Just spent 3 hours trying to figure this one out, hope it helps someone 🙂

Tested in:

  • IE 7.5730.11
  • Mozilla Firefox 1.81

Later on in July 2010 in a related answer Arctic Fire then linked two further user-notes that were-follow-ups to the one above:

More Related Contents:

  1. How do I run ajax request in background continuously?
  2. Tagging systems [closed]
  3. How to use this code my wordpress theme
  4. how to do file upload using jquery serialization
  5. How to get the jQuery $.ajax error response text?
  6. Send array with Ajax to PHP script
  7. Get response from PHP file using AJAX
  8. PHP/Apache/AJAX – POST limit?
  9. Jquery/Ajax Form Submission (enctype=”multipart/form-data” ). Why does ‘contentType:False’ cause undefined index in PHP?
  10. HTML – Change\Update page contents without refreshing\reloading the page
  11. Ajax passing data to php script
  12. jQuery AJAX form using mail() PHP script sends email, but POST data from HTML form is undefined
  13. Passing Javascript Variable to PHP using Ajax
  14. Ajax post request in laravel 5 return error 500 (Internal Server Error)
  15. Inserting into MySQL from PHP (jQuery/AJAX)
  16. Retrieve JSON POST data in CodeIgniter
  17. Jquery – Uncaught TypeError: Cannot use ‘in’ operator to search for ‘324’ in
  18. Pass data from jQuery to PHP for an ajax post
  19. Jquery ajax setTimeout after form succes not redirecting?
  20. Ajax call with contentType: ‘application/json’ not working
  21. jQuery Ajax passing value on php same page
  22. How to rotate image and save the image
  23. Cross Domain Ajax Request with JQuery/PHP
  24. When do I use PHP_EOL instead of \n and vice-versa ? Ajax/Jquery client problem
  25. Codeigniter CSRF valid for only one time ajax request
  26. Ajaxify header cart items count in Woocommerce
  27. boolean variables posted through AJAX being treated as strings in server side
  28. json_encode not working with a html string as value
  29. How to implement a chat room using Jquery/PHP?
  30. How to Load Ajax in WordPress

Leave a Comment