UnixCommands/Kill

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NAME
       kill - send signals to processes, or list signals

SYNOPSIS

       kill [ -s signal | -p ] [ -a ] [ -- ] pid ...
       kill -l [ signal ]

see: "man kill"

-l     Print   a   list   of   signal   names.    These  are  found  in
              /usr/include/linux/signal.h

---

 1) SIGHUP       2) SIGINT       3) SIGQUIT      4) SIGILL
 5) SIGTRAP      6) SIGABRT      7) SIGBUS       8) SIGFPE
 9) SIGKILL     10) SIGUSR1     11) SIGSEGV     12) SIGUSR2
13) SIGPIPE     14) SIGALRM     15) SIGTERM     17) SIGCHLD
18) SIGCONT     19) SIGSTOP     20) SIGTSTP     21) SIGTTIN
22) SIGTTOU     23) SIGURG      24) SIGXCPU     25) SIGXFSZ
26) SIGVTALRM   27) SIGPROF     28) SIGWINCH    29) SIGIO
30) SIGPWR      31) SIGSYS      35) SIGRTMIN    36) SIGRTMIN+1
37) SIGRTMIN+2  38) SIGRTMIN+3  39) SIGRTMIN+4  40) SIGRTMIN+5
41) SIGRTMIN+6  42) SIGRTMIN+7  43) SIGRTMIN+8  44) SIGRTMIN+9
45) SIGRTMIN+10 46) SIGRTMIN+11 47) SIGRTMIN+12 48) SIGRTMIN+13
49) SIGRTMIN+14 50) SIGRTMAX-14 51) SIGRTMAX-13 52) SIGRTMAX-12
53) SIGRTMAX-11 54) SIGRTMAX-10 55) SIGRTMAX-9  56) SIGRTMAX-8
57) SIGRTMAX-7  58) SIGRTMAX-6  59) SIGRTMAX-5  60) SIGRTMAX-4
61) SIGRTMAX-3  62) SIGRTMAX-2  63) SIGRTMAX-1  64) SIGRTMAX

---

No no no. Don't use kill -9.

It doesn't give the process a chance to cleanly:

1) shut down socket connections

2) clean up temp files

3) inform its children that it is going away

4) reset its terminal characteristics

and so on and so on and so on.

Generally, send 15, and wait a second or two, and if that doesn't work, send 2, and if that doesn't work, send 1. If that doesn't, REMOVE THE BINARY because the program is badly behaved!

Don't use kill -9. Don't bring out the combine harvester just to tidy up the flower pot.

Just another Useless Use of Usenet

from: "Useless use of "kill -9"-awards: by Randal"

http://groups.google.com/groups?oi=djq&as_usubject=useless+use+kill&num=25

Table of contents

pkill

NAME

kill - send a signal to a process

SYNOPSIS

kill [ -signal | -s signal ] pid ...
kill [ -L | -V, --version ]
kill -l [ signal ]

DESCRIPTION

The default signal for kill is TERM. Use -l or -L to list available signals. Particularly useful signals include HUP, INT, KILL, STOP, CONT, and 0. Alternate signals may be specified in three ways: -9 -SIGKILL -KILL. Negative PID values may be used to choose whole process groups; see the PGID column in ps command output. A PID of -1 is special; it indicates all processes except the kill process itself and init.

SIGNALS

The signals listed below may be available for use with kill. When known constant, numbers and default behavior are shown.

Name	Num	Action	Description
0	0	n/a	exit code indicates if a signal may be sent
ALRM	14	exit
HUP	1	exit
INT	2	exit
KILL	9	exit	this signal may not be blocked
PIPE	13	exit
POLL		exit
PROF		exit
TERM	15	exit
USR1		exit
USR2		exit
VTALRM		exit
STKFLT		exit	may not be implemented
PWR		ignore	may exit on some systems
WINCH		ignore
CHLD		ignore
URG		ignore
TSTP		stop	may interact with the shell
TTIN		stop	may interact with the shell
TTOU		stop	may interact with the shell
STOP		stop	this signal may not be blocked
CONT		restart	continue if stopped, otherwise ignore
ABRT	6	core
FPE	8	core
ILL	4	core
QUIT	3	core
SEGV	11	core
TRAP	5	core
SYS		core	may not be implemented
EMT		core	may not be implemented
BUS		core	core dump may fail
XCPU		core	core dump may fail
XFSZ		core	core dump may fail

NOTES

Your shell (command line interpreter) may have a built-in kill command. You may need to run the command described here as /bin/kill to solve the conflict.

EXAMPLES

kill -9 -1: Kill all processes you can kill.
kill -l 11: Translate number 11 into a signal name.
kill -L: List the available signal choices in a nice table.
kill 123 543 2341 3453: Send the default signal, SIGTERM, to all those processes.

STANDARDS

This command meets appropriate standards. The -L flag is Linux-specific.

AUTHOR

Albert Cahalan <albert@users.sf.net> wrote kill in 1999 to replace a bsdutils one that was not standards compliant. The util-linux one might also work correctly.

Please send bug reports to <procps-feedback@lists.sf.net>