Comments on: PHP Exclusive Single Process Mutex

By: Thomas Hruska

Thomas Hruska — Mon, 11 Oct 2010 18:14:17 +0000

That is very similar to my solution:

http://cubicspot.blogspot.com/2010/10/forget-flock-and-system-v-semaphores.html

By: Robert

Robert — Sat, 12 Sep 2009 14:23:38 +0000

I use this for some time now

function mutex($mtx, $i)
{
	switch($i){
	case 0: @unlink($mtx); return;
	case 1: while(!($fp = @fopen($mtx,'x'))){ } fclose($fp); return;
	case 2: $fp=@fopen($mtx,'x'); if($fp){ fclose($fp); return 1; } return 0;
	}
}

By: Elliott Back

Elliott Back — Sun, 07 Jun 2009 03:55:08 +0000

Yeah, my web runs via apache. But the lockfile is owned as apache. Interestingly, I just tried it again and it worked on the web (because another was running via cron). Hmm…

By: Montoya

Montoya — Fri, 05 Jun 2009 02:35:29 +0000

Could it be a permissions issue? Usually when running a php file on the command line, you are running as root, but via the web, you might be running as Apache or as nobody.