Best way to kill all child processes forked by a given program

Best way to kill all child processes forked by a given program

Answer:

Firstly, find the process group leader (i.e. master process that forked other processes) of the program, e.g. apache2

# sudo ps x -o  "%p %r %y %x %c " | grep apache2 

14787 14787 ?        00:00:00 apache2

To verify if it is the process leader.

# pgrep apache2 | sort -n | head -n1 
14787 

To issue kill to all the members in the process group

# kill -9 -14787