Question

How to create unstoppable while loop,
if it’s already running dont run it again, I assume that if script running it will update last cron time in database, and script will check if current time – 40 seconds is less than last cron time. Sample of what I’ve, but that’s overlooping ( running again and again do process ) Thanks!

<?php
ignore_user_abort(1); // run script in background 
set_time_limit(0);    // set limit to 0


function processing()
{
//some function here
setting::write('cron_last_time', $time); // write cron last time to database
}

$time = current_timestamp();  // current time
$time_before = $time - 20;   //

$settings = setting::read('module_cron_email'); // Get last cron time from database ( in array )
$time_last = $settings['setting_value'];     // Last cron time get value from array



if ($time_before < $time_last) // check if time before is less than last cron time
{ 
   do{
   processing(); //run our function
   sleep(7);    // pause for 7 seconds
   continue;   // continue
   }
   while(true); // loop
}else{

echo "already running";
die();
}
?> 

Answer 1

When starting the script, check for a lock file. If it does exist, quit or skip the loop. If it doesn’t exist, create the file and let it run.