I wanted to implement Comet in PHP and came across this page:
http://www.zeitoun.net/articles/comet_and_php/start
The second method explained in the article works fine for me. In the backend php file, the loop seems to be infinite:
// infinite loop until the data file is not modified
$lastmodif = isset($_GET['timestamp']) ? $_GET['timestamp'] : 0;
$currentmodif = filemtime($filename);
while ($currentmodif <= $lastmodif) // check if the data file has been modified
{
usleep(10000); // sleep 10ms to unload the CPU
clearstatcache();
$currentmodif = filemtime($filename);
}
When the client leaves the page, how to tell the server to stop processing the loop? Otherwise I fear that the loop is going to go on and on on the server until something is modified.