Send a signal to processes or reset the priority. The default signal for skill is TERM, and the default priority for snice is +4 but can be in the range +20 (slowest) to -20 (fastest). The selection options -c, -p, -t, and -u are not required, but can be specified to insure that processes are interpreted correctly.
The next argument is a command.
Use interactive mode.
List available signals.
Display the process ID, but take no other action.
The next argument is a process ID.
The next argument is a tty or pty.
The next argument is a username.