Handling the signal generated by system reboot

Question

Whenever I give reboot command, my process is receiving SIGTERM signal and is handling it. I don't want to handle it if the SIGTERM is due to reboot.

Please suggest me any idea.

Is there any way to send kill -9 signal to my process when I do system("reboot")?

I am using Cent OS (Linux).

Answer 1

whenever i give reboot command,my process is receiving SIGTERM signal and is handling it. I dont want to handle it if the SIGTERM is due to reboot.

You may try to run /sbin/runlevel in your signal handler (well, maybe process spawning is not even possible in a signal handler though) to get the current runlevel. Runlevel 6 is reboot.

Is there any way to send kill -9 signal to my process when i do system(reboot).

If your process is started by init scripts you can change the script so that stop is performed with kill -KILL instead of something else.

I am using Cent OS(linux).

I don't know if the following applies for CentOS.

In Debian, all remaining processes (the ones alive after all kill scripts have been ran) are signaled by /etc/init.d/sendsigs. If you have administrator access you can try to customize it so a specially named process (yours) get KILLed without TERMing before.

Still, all pids related in /run/sendsigs.omit and all pids related in files in /run/sendsigs.omit.d/ don't receive any signal.