How to trace the process id and killl it together with its child processes.

bpteoh · 01-13-2009, 12:35 AM

I got one prewriten C application, which can run multiple instance in linux, each will occupied a port for data transfering.
In some case when certain port is not working, i need to kill the process, including all its child processes and restart it.

How should i do it? i was thinking to write a script to trace all the process id with its child process , write in a file and kill it when needed. but i don't know how i suppose to write.

chakka.lokesh · 01-13-2009, 12:44 AM

Quote:

Originally Posted by bpteoh

How should i do it? i was thinking to write a script to trace all the process id with its child process , write in a file and kill it when needed.

check pstree command. may be it is helpful to you.....

firstfire · 01-13-2009, 04:40 AM

Hi, bpteoh.

Try the following bash script:

Code:

#!/bin/bash
# file: listchild.sh
# Usage: listchild.sh PID

#set -x

: ${start:=$1}
while [ -n "$start" ];
do
	echo $start; 
	# replace spaces/newlines by commas
	start=`echo "$start"| tr '\n' ' ' |sed 's/ \+/,/g'`;
	# eat up leading comma
	start=${start:0:((${#start}-1))};
	start=`pgrep -P$start`;
done

Uncomment 'set -x' line to see how the script works. Command `pgrep -P<comma-separated-list-of-pids>' will print newline-separated list of pids, whose parents were listed. On Debian system pgrep can be found in the procps package.

Command `ps -Af --forest` may be useful for checking the result.

To kill all child processes of given one, type:

Code:

kill `./listchild.sh PID`