/usr/sbin/killall [- | [-]signal_name | -signal_number]
In the System V habitat, the optional signal number does not have to be preceded with a hyphen (-). Lists signal names in numerical order (as given in the /usr/include/signal.h file), stripped of the common SIG prefix.
This command provides a convenient means of killing all processes created by the shell that you control. When started by the superuser, the killall command kills all processes that can be terminated, except those processes that started it, the kernel processes, and processes 0 and 1 (init).
To stop all background processes that have started, enter: killall This sends all background processes signal 9 (the kill signal, also called SIGKILL). To stop all background processes, giving them a chance to clean up, enter: killall - This sends signal 15 (SIGTERM), waits 30 seconds, and then sends signal 9 (SIGKILL). To send a specific signal to the background processes, enter: killall -2 This sends signal 2 (SIGINT) to the background processes. To list the signal names in numerical order, stripped of the SIG prefix, enter: killall -l This displays a list of signals, which may vary from system to system.
Calls: kill(2), sigaction(2), signal(2) delim off