从精美的手册页:
kill [-s sigspec | -n signum | -sigspec] [pid | jobspec] ...
kill -l [sigspec | exit_status]
Send the signal named by sigspec or signum to the processes named by pid or
jobspec. sigspec is etc. etc....
那么是什么决定了是kill 1
杀死init进程还是jobspec 1呢?