<?php
$time= time();
require('../ConcurrentFile.php');
if ($_POST) {
// do stuff
$file = new ConcurrentFile("data.txt");
$file->writeLock();
sleep(20);
$file->write("hello world old");
$file->close();
}
?>
<html>
<head><title>race condition example</title></head>
<body>
<p>This is a test to see the transaction at work.</p>
<p>click on the button "do stuff", while page is loading remove the code "sleep(20)" and change "old" to "right", then click in a new tab the same button </p>
<p>You will see that the second script will wait for the end of first script and the result is right</p>
<form method="POST">
Delay caused by lock <?php echo time() - $time; ?> , max is 20.<br>
<a><?php echo ConcurrentFile::getInstance("data.txt")->read(); ?></a>
<input type="submit" name="do_stuff" value="Do stuff!">
</form>
</body>
</html>
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