如何检查php脚本是否已经运行

Question

如何创建不可阻挡的while循环,如果它已经运行不再运行它,我假设如果运行它的脚本将更新数据库中的最后cron时间,脚本将检查当前时间 - 40秒是否小于上一个cron时间.我所拥有的样本,但那是过度循环(一次又一次地运行)谢谢!

<?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

启动脚本时,请检查锁定文件.如果确实存在,则退出或跳过循环.如果它不存在,请创建该文件并让它运行.