builtin help kill

[shoebill]

kill: kill [-s sigspec | -n signum | -sigspec] pid | jobspec ... or kill -l [sigspec]
    Send a signal to a job.

    Send the processes identified by PID or JOBSPEC the signal named by
    SIGSPEC or SIGNUM.  If neither SIGSPEC nor SIGNUM is present, then
    SIGTERM is assumed.

    Options:
      -s sig    SIG is a signal name
      -n sig    SIG is a signal number
      -l        list the signal names; if arguments follow `-l' they are
        assumed to be signal numbers for which names should be listed

    Kill is a shell builtin for two reasons: it allows job IDs to be used
    instead of process IDs, and allows processes to be killed if the limit
    on processes that you can create is reached.

    Exit Status:
    Returns success unless an invalid option is given or an error occurs.