awk 'system()' vs xargs

Two different syntaxes for processing a command over a list of arg.

Let's take for example, the list of PID you want to kill(all the processes matching "toto") :

ps | grep toto | awk -F' ' '{print $2}' | xargs kill -9

is equivalent to

ps | grep toto | awk -F' ' '{system("kill -9 "$2}'

note that the space at the end of the string "kill -9 " is important since the $2 will be concatenated.