php forking issue

Question

I have the following test php to do a fork/spawn process, where the test also attempts to kill the child process (zombie) after is completes..

I\'d like to have a more e

Answer 1

Just use pcntl_wait(). There's no need to see if the child process has finished, just call pcntl_wait() and block until the child is reaped.

Avoid passing WNOHANG so that your parent process will sit and wait for a child to finish.

You can replace the reaping code you've written (starting at line 58 '$q=true;' of your example) with this:

$status = null;

do {
    // You can use $status with pcntl_wifexited(), pcntl_wifstopped(),
    // pcntl_wifsignaled(), pcntl_wexitstatus(), pcntl_wtermsig() and
    // pcntl_wstopsig() if you need to.

    $pid = pcntl_wait($status);

} while ($pid > 0);

Answer 2

Fork in foreach:

<?
declare(ticks=1);
pcntl_signal(SIGUSR1, create_function('$signo', 'sleep(1);while (($pid=pcntl_wait(@$status, WNOHANG))>0) {}'));//protect against zombie children
foreach ($tasks as $v)
        {if (($pid=pcntl_fork())===-1)
            {//...
             continue;
            }
         else if ($pid===0)
              {ob_start();//prevent output to main process
               register_shutdown_function(create_function('$pars', 'ob_end_clean();posix_kill(posix_getppid(), SIGUSR1);posix_kill(getmypid(), SIGKILL);'), array());//to kill self before exit();, or else the resource shared with parent will be closed
               //...
               exit();//avoid foreach loop in child process
              }
        }
?>