checking if a process exists

[sde]

On my game servers, I have a stats program written in perl running in the background. It listens for log information that is sent from Half-Life.

Since the perl script runs in the background, it is difficult to determine if it is running unless I ssh in and execute:

ps aux |grep hlstats.pl

so now i want to make a script that i can view from a web page that verifies that the process is running.

here is how i start the script:

-nohup ./hlstats.pl &

i'd prefer to be able to do this all in php, however i haven't been able to get info back from an exec() command in php.

can anyone suggest what they think is the best way to accomplish this?

[joe_bruin]

try the popen() function instead of exec().

[sdeming]

1. Have hlstats.pl write it's PID to /var/run/hlstats.pl.pid
2. Have your PHP script read PID from the /var/run/hlstats.pl.pid file
3. Look in /proc/PID to see if the process is still active.

Works good this way.

[sde]

great thinking! =) thanks..

now i'm not sure how to have the hlstats.pl script write its own pid.

[sdeming]

In perl, use the predefined variable $$, for example:

print "PID: $$\n";

[schotty]

Would this link be of interest?

Half life daemon