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copied!<p>Here's one solution, not the greatest, but will work fine on Linux:</p> <p>Split the processing PHP into a separate CLI scripts in which: </p> <ul> <li>The command line inputs include `$id` and `$item` <li>The script writes its PID to a file in `/tmp/$id.$item.pid` <li>The script echos results as XML or something that can be read into PHP to stdout <li>When finished the script deletes the `/tmp/$id.$item.pid` file </ul> <p>Your master script (presumably on your webserver) would do: </p> <ul> <li>`exec("nohup php myprocessing.php $id $item > /tmp/$id.$item.xml");` for each item <li>Poll the `/tmp/$id.$item.pid` files until all are deleted (sleep/check poll is enough) <li>If they are never deleted kill all the processing scripts and report failure <li>If successful read the from `/tmp/$id.$item.xml` for format/output to user <li>Delete the XML files if you don't want to cache for later use </ul> <p>A backgrounded <code>nohup</code> started application will run independent of the script that started it.</p> <p>This interested me sufficiently that I decided to write a POC.</p> <p>test.php</p> <pre><code><?php $dir = realpath(dirname(__FILE__)); $start = time(); // Time in seconds after which we give up and kill everything $timeout = 25; // The unique identifier for the request $id = uniqid(); // Our "items" which would be supplied by the user $items = array("foo", "bar", "0xdeadbeef"); // We exec a nohup command that is backgrounded which returns immediately foreach ($items as $item) { exec("nohup php proc.php $id $item > $dir/proc.$id.$item.out &"); } echo "<pre>"; // Run until timeout or all processing has finished while(time() - $start < $timeout) { echo (time() - $start), " seconds\n"; clearstatcache(); // Required since PHP will cache for file_exists $running = array(); foreach($items as $item) { // If the pid file still exists the process is still running if (file_exists("$dir/proc.$id.$item.pid")) { $running[] = $item; } } if (empty($running)) break; echo implode($running, ','), " running\n"; flush(); sleep(1); } // Clean up if we timeout out if (!empty($running)) { clearstatcache(); foreach ($items as $item) { // Kill process of anything still running (i.e. that has a pid file) if(file_exists("$dir/proc.$id.$item.pid") && $pid = file_get_contents("$dir/proc.$id.$item.pid")) { posix_kill($pid, 9); unlink("$dir/proc.$id.$item.pid"); // Would want to log this in the real world echo "Failed to process: ", $item, " pid ", $pid, "\n"; } // delete the useless data unlink("$dir/proc.$id.$item.out"); } } else { echo "Successfully processed all items in ", time() - $start, " seconds.\n"; foreach ($items as $item) { // Grab the processed data and delete the file echo(file_get_contents("$dir/proc.$id.$item.out")); unlink("$dir/proc.$id.$item.out"); } } echo "</pre>"; ?> </code></pre> <p>proc.php</p> <pre><code><?php $dir = realpath(dirname(__FILE__)); $id = $argv[1]; $item = $argv[2]; // Write out our pid file file_put_contents("$dir/proc.$id.$item.pid", posix_getpid()); for($i=0;$i<80;++$i) { echo $item,':', $i, "\n"; usleep(250000); } // Remove our pid file to say we're done processing unlink("proc.$id.$item.pid"); ?> </code></pre> <p>Put test.php and proc.php in the same folder of your server, load test.php and enjoy.</p> <p>You will of course need nohup (unix) and PHP cli to get this to work.</p> <p>Lots of fun, I may find a use for it later.</p>

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