I am writing a php code for remote controlling some processes and devices that are connected to a linux pc. The codes are written in python. I can run the scripts and programs usnig php functions such as exec() or system() but I can not kill my processes.
I want to kill the python:
<?php
$PID = exec("pidof python");
echo $PID;
$kill = "kill " . $PID;
exec($kill);
?>
It returns the correct PID number but does not kill the process.
I also tried exec("kill #PIDnum"); but it does not work.
Any suggestions?
Thanks in advance
You can only kill processes from PHP that are owned by the userid running the web server on your system, which is usually set to a low-privilege account like "nobody", "www", web", etc.
It could work if the python were started from a PHP script. But otherwise, no.
A work around is to append lines to a file from PHP, the file to contain a list of the PIDs to be killed. This won't kill the processes, you will need to write a separate script to do that, in a language like bash or perl, python, etc. Have cron run that script as root, to periodically read the file, and kill the PIDs. But then, it won't be instantaneous. You could set up cron to run such a script every minute, though.
Related
I have a file named /root/folder/myfile.php that will handle incoming packets from a specific port by a GPS device.
When I use [root#main ~] php /root/folder/myfile.php, everything works fine.
I need this file run every second to listen.
I researched for a while and figured out that using php cli is a solution, so I tried above command but as long as the shell is open (I'm using PUTTY), file is executing and when I close the shell, process will be killed.
How can I (where can I) add a command that will run this file every second, or may be in realtime?
I'm using linux centOS 6.5.
Thanks in advance
nohup php myscript.php &
the & puts your process in the background.
The solution from Run php script as daemon process
To kill it:
1) display all running proceses with: ps aux | less or top command
2) find pid(process id) and kill with: kill pid
You would want to use the cron functionality of your server.
Similar to this maybe:
running a script from cron every second
I have centos VPS hosting and installed WHM/cPanel . I want to run a php script using command line for unlimited time.
My script is look like:
<?php
set_time_limit(0);
while(true)
{
//code to send me email
sleep(600);
}
?>
I know that this script should be run for unlimited time.
I have used these commands:
php myfile.php &
nohup php myfile.php &
I found these commands on stackoverflow. And these are running fine. But after one hours, It stop automatically.
I think, i am doing right. But i do not know, which is killing that process.
If not,
i want to know that How to run this script for unlimited time.
What you are doing is correct. It should run. I have PHP scripts that run for much longer than an hour. They run for days on end. I also have programs that are not PHP that should run forever, but don't. It is because they die due to a bug in the program. For example, xscreensaver dies on me about once a week. To keep it running, I use this shell script (which you can use to keep your PHP running):
while:
do
xscreensaver &
wait
done
Now, running that shell script will start the program again if it ever dies for any reason.
If you have console access try using cronjob to run this file.
see : https://www.centos.org/docs/5/html/Deployment_Guide-en-US/ch-autotasks.html
also : http://alvinalexander.com/linux/linux-crontab-file-format-example
Make sure you use php-command in cron-job
Note : You'll require admin rights to edit/work with cron-jobs
I'm starting my php script in the following way:
bash
cd 'path'
php -f 'scriptname'.php
There is no output while the php script is running.
After a time, the php script responds with:
Killed
My idea is that it reached the memory_limit: ini_set('memory_limit', '40960M');
Increasing the memory limit seemed to solve the problem, but it only increased the edge.
What exactly does that Killed phrase mean?
Your process is killed. There could be a multitude of reasons, but it's easy to discard some of the more obvious.
php limits: if you run into a php limit, you'll get an error in the logfile, and probably on the commandline as well. This normally does not print 'killed'
the session-is-ended-issues: if you still have your session, then your session is obvioiusly not ended, so disregard all the nohup and & stuff
If your server is starved for resources (no memory, no swap), the kernel might kill your process. This is probably what's happening.
In anycase: your process is getting send a signal that it should stop. Normally only a couple of 'things' can do this
your account (e.g. you kill the process)
an admin user (e.g. root)
the kernel when it is really needing your memory for itself.
maybe some automated process, for instance, if you live on a shared server and you take up more then your share of resources.
references: Who "Killed" my process and why?
You could be running out of memory in the PHP script. Here is how to reproduce that error:
I'm doing this example on Ubuntu 12.10 with PHP 5.3.10:
Create this PHP script called m.php and save it:
<?php
function repeat(){
repeat();
}
repeat();
?>
Run it:
el#apollo:~/foo$ php m.php
Killed
The program takes 100% CPU for about 15 seconds then stops. Look at dmesg | grep php and there are clues:
el#apollo:~/foo$ dmesg | grep php
[2387779.707894] Out of memory: Kill process 2114 (php) score 868 or
sacrifice child
So in my case, the PHP program printed "Killed" and halted because it ran out of memory due to an infinite loop.
Solutions:
Increase the amount of RAM available.
Break down the problem set into smaller chunks that operate sequentially.
Rewrite the program so it has a much smaller memory requirements.
Killed is what bash says when a process exits after a SIGKILL, it's not related to putty.
Terminated is what bash says when a process exits after a a SIGTERM.
You are not running into PHP limits, you may be running into a different problem, see:
Return code when OOM killer kills a process
http://en.wikipedia.org/wiki/Nohup
Try using nohup before your command.
nohup catches the hangup signal while the ampersand doesn't (except the shell is confgured that way or doesn't send SIGHUP at all).
Normally, when running a command using & and exiting the shell afterwards, the shell will terminate the sub-command with the hangup signal (kill -SIGHUP ). This can be prevented using nohup, as it catches the signal and ignores it so that it never reaches the actual application.
In case you're using bash, you can use the command shopt | grep hupon to find out whether your shell sends SIGHUP to its child processes or not. If it is off, processes won't be terminated, as it seems to be the case for you.
There are cases where nohup does not work, for example when the process you start reconnects the NOHUP signal.
nohup php -f 'yourscript'.php
If you are already taking care of php.ini settings related with script memory and timeout then may be its linux ssh connection which terminating in active session or some thing like that.
You can use 'nohup' linux command run a command immune to hangups
shell> nohup php -f 'scriptname'.php
Edit:- You can close your session by adding '&' at end of command:-
shell> nohup php -f 'scriptname'.php &> /dev/null &
'&' operater at end of any comand in linux move that command in background
I wrote a shell script in linux to check if one of my program (say programA) is running, if it stopped, it will restart the program.
ok, I also have a php script which hav start & stop button to start and stop the same program from the server side. If the program is already run by the shell script, clicking on start button will NOT run multiple of the same program.
THE PROBLEM IS: if PHP script works fine by itself. But the PHP script cannot close the program if it is run by the shellscript. Is this a permission issue or something that I havent been aware of? (I already did chmod 777 programA btw...)
UPDATE:
in my PHP script, it calls exec("kill -9 PID_of_programA") to kill the program.
I tried to change it to $r = shell_exec("kill -9 PID_of_programA") and echo $r gives me nothing...
You are probably running your program with a user that has no privileges to close other programs... Have you tried to run as super user?
I have a large PHP application and I'm looking for a way to know which PHP script is running at a given moment. Something like when you run "top" on a Linux command line but for PHP.
Are you trying to do so from within the PHP application, or outside of it? If you're inside the PHP code, entering debug_print_backtrace(); at that point will show you the 'tree' of PHP files that were included to get you at that point.
If you're outside the PHP script, you can only see the one process that called the original PHP script (index.php or whatnot), unless the application spawns parallel threads as part of its execution.
If you're looking for this information at the system level, e.g. all php files running under any Apache child process, or even any PHP files in use by other apps, there is the lsof program (list open files), which will spit out by default ALL open files on the system (executables, sockets, fifos, .so's, etc...). You can grep the output for '.php' and get a pretty complete picture of what's in use at that moment.
This old post shows a way you can wrap your calls to php scripts and get a PID for each process.
Does PHP have threading?
$cmd = 'nohup nice -n 10 /usr/bin/php -c /path/to/php.ini -f /path/to/php/file.php action=generate var1_id=23 var2_id=35 gen_id=535 > /path/to/log/file.log & echo $!';
$pid = shell_exec($cmd);