note 103789 deleted from function.posix-getpgid by danbrown
| From: | danbrown@php.net | Date: | Wed, 04 May 2011 17:00:39 +0000 |
| Subject: | note 103789 deleted from function.posix-getpgid by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-179425@lists.php.net to get a copy of this message | ||
Note Submitter: Robert Mays Jr
----
This function and posix_getsid can be used to check if a process is alive (since they return FALSE
if the process can not be found)
So if you have a PID in a lock file, and you want to know if that process is still running- you can
use this code:
<?php
$lockfile = sys_get_temp_dir() . '/myScript.lock';
$pid = file_get_contents($lockfile);
if (posix_getsid($pid) === false) {
print "process has died! restarting...\n";
file_put_contents($lockfile, getmypid()); // create lockfile
} else {
print "PID is still alive! can not run twice!\n";
exit;
}
?>
:-) perfect if you need to make sure a cron job or shell script has ended before it can be started
again.