Re: Re: process creation

Török Alpár wrote:

2009/1/23 Nathan Rixham <nrixham@gmail.com>

bruce wrote:

A simple question (or so I thought). Does php allow an app to create/start a process/application that can continue to run on its own, after the initiating program/app terminates? It appears that the spawning/forking functions might work, but the child apps would be in a zombie status, and couldn't be killed by an external program.

you keep mentioning this zombie state; make sure that all you're child processes have an exit(); at the end or at the end of the code where they are finished; otherwise you get the xombies! also here is a very simple model you can follow that invariably works for me: this will run 10 worker threads: controller: <?php include './your.framework.php'; for($icount=0;$icount<11;$icount++) { include './worker.php'; } ?> worker: <?php $pid=pcntl_fork(); if(!$pid) { while(1) {

       if($icount) {
           $offset = $icount * 50;
       } else {
           $offset = 0;
       }
       $db = new mysql_handler( $connection );
       $job_list = new job_list;
       if( $jobs = $job_list->get($offset) ) {
           foreach($jobs as $jdex => $job ) {
               //do something with the job
           }
       } else {
           sleep(10);
       }

} } else { echo "\ndaemon launcher done id $pid\n"; } ?>

This would start more than 10 children. Children will continue on with for loop after they do their work. As you advice that the children have an exit, i assume that you just overlooked it while writing this example. Also, a wait on the children, at some point, gets rid of the zombies, as i see from your code, there is no way you won't have zombie processes, unless the parent exists, and then the zombies also disappear. I hope i got it right, it's late here :)

lol the script will only run 10 children, and as mentioned directly below, it is designed to run forever - the example doesn't fit the exact needs, but following bruces earlier posts this may be a model he can follow. I'm aware it could be fleshed out with much more code and error handling, but it's just a little model to get one started :) regards torak and hope you're well!

the above code is designed to run indefinately in a constant loop which polls a database for work to do this is just a very simple example, there are far more complex ways of doing it, keeping a track of how many processes you have, spawning new ones when you need them etc etc, but this i find works v well for me, the key is the $offset; getting jobs from a database and this literally is the offset used, so if you have say 200 emails to get and each script processes 50 at a time, only 4 of your threads are working, bump it up to 10000 and all of them work until the queue drops; the sleep(10) and the spawn process of about 1 per second ensures that you're polling every second so jobs are picked up quickly. it's a lot of functionality for so little code :) -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php