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kill(1)								      kill(1)



NAME

  kill - Sends a signal	to a running process

SYNOPSIS

  kill -l  [exit_status]

  kill [-signal_name  |	signal_number] process_ID...

  kill -s  signal_name process_ID...

				     Note

       The C shell has a built-in version of the kill command.	If you are
       using the C shell, and want to guarantee	that you are using the com-
       mand described here, you	must specify the full path /usr/bin/kill.
       See the csh(1) reference	page for a description of the built-in com-
       mand.

STANDARDS

  Interfaces documented	on this	reference page conform to industry standards
  as follows:

  kill:	 XCU5.0

  Refer	to the standards(5) reference page for more information	about indus-
  try standards	and associated tags.

OPTIONS

  The kill command supports the	following options:

  -l  Lists signal names.

      If you specify an	exit status (a numeric value) or the shell special
      parameter	$?, which expands to the exit status of	the most recent	pipe-
      line, kill prints	the name of the	terminating signal.

  -s signal_name
      Specifies	the signal to send, using one of the symbolic names defined
      for required signals or job control signals.  Values of signal_name are
      recognized in both uppercase or lowercase	letters, and without the SIG
      prefix.  The symbolic name 0 (zero), which represents the	value 0
      (zero), is also recognized.  The corresponding signal is sent instead
      of SIGTERM.

  -signal_name | -signal_number
      Specifies	the signal to send to the process.  You	can specify either a
      name, stripped of	the SIG	prefix (such as	KILL), or a number (such as
      9).  For information about signal	names and numbers, see the sigac-
      tion() system call.







OPERANDS

  process_ID
      A	process	identification number

      [Tru64 UNIX]  There are several special process identification numbers
      (PIDs) that you can specify to cause the following special actions:

      0	  The signal is	sent to	all processes having a process group ID	equal
	  to the process group ID of the sender, except	those with a process
	  ID of	0 (zero) and the process ID of the init	process.

	  Signals using	this PID do not	span cluster members.

      -1  If the effective user	ID of the sender is not	0 (root), the signal
	  is sent to all processes with	a process group	ID equal to the
	  effective user ID of the sender, except those	with a process ID of
	  0 (zero) and the process ID of the init process.

	  If the effective user	ID of the sender is 0 (root), the signal is
	  sent to all processes	(on the	current	member if a cluster), except
	  the process ID of 0 (zero) and the process ID	of the init process.

	  Signals using	this PID do not	span cluster members.

      -PID
	  The signal is	sent to	all processes whose process group number is
	  equal	to the absolute	value of PID. This is true even	in the case
	  of a cluster where the process to receive the	signal is on another
	  cluster member.  Note	that when you specify any negative PID,	you
	  must also specify the	signal to be sent, even	the default signal
	  SIGTERM.

  exit_status
      A	decimal	integer	specifying a signal number or the exit status of a
      process terminated by a signal.

DESCRIPTION

  The kill command sends a signal to one or more running processes.  The
  default is the SIGTERM signal	(signal	number 15), which usually terminates
  processes that do not	ignore or catch	the signal.

  You identify the process to be signaled by specifying	its process identifi-
  cation number	(also known as the process ID or PID). The shell displays the
  PID of each process that is running in the background	or, if you start more
  than one process in a	pipeline, the shell displays the number	of the last
  process.  You	can also use the ps command to display PIDs.

  [Tru64 UNIX]	The name of the	kill command is	misleading because many	sig-
  nals,	including SIGUSR1, do not terminate processes.

  [Tru64 UNIX]	Unless you are operating with superuser	privileges, the	pro-
  cess you want	to signal must belong to you.  When operating with superuser
  authority, you can signal any	process.

  [Tru64 UNIX]	See the	kill() system call for a complete discussion of	kill.
  Note that the	csh command contains a built-in	subcommand named kill, but
  the command and subcommand do	not necessarily	work in	the same way.  For
  information on the subcommand, see csh.

  [Tru64 UNIX]	In a TruCluster	Server cluster,	if the passed parameter	is
  greater than zero (0), the signal is sent to the process whose PID matches
  the passed parameter,	no matter on which cluster member it is	running.  If
  the passed parameter is less than -1,	the signal is sent to all processes
  (cluster-wide) whose process group ID	matches	the absolute value of the
  passed parameter.

NOTES

  Some applications and	scripts	depend on the process ID of the	init program
  being	1 (one):  do not depend	on it.	Instead, use standard methods, such
  as the ps and	grep commands, to obtain all process IDs.

EXIT STATUS

  The following	exit values are	returned:

  0   At least one matching process was	found, and the specified signal	was
      successfully processed for at least one matching process.

  >>0  An error occurred.

EXAMPLES

   1.  The following command terminates	the process with the specified PID:
	    kill 1095

       This command terminates process 1095 by sending it the default SIGTERM
       signal.	Note that process 1095 might not actually terminate if it has
       made special arrangements to ignore or catch the	SIGTERM	signal.

   2.  The following command terminates	several	processes that ignore the
       default signal:
	    kill -KILL 17285 15692

       This command sends SIGKILL to processes 17285 and 15692.	The SIGKILL
       signal usually cannot be	ignored	or caught.

   3.  The following command terminates	all of your background processes.
       Signals using this PID do not span cluster members.
	    kill 0

       This command sends the SIGTERM signal to	all members of the shell pro-
       cess group. This	includes all background	processes started with &&.
       Although	the signal is sent to the shell, it has	no effect because the
       shell ignores the default signal	15.

   4.  The following command terminates	all of your processes and logs you
       out.  Signals using this	PID do not span	cluster	members.
	    kill -KILL 0

       This command sends SIGKILL to all members of the	shell process group.
       Because the shell cannot	ignore SIGKILL,	this also terminates the
       login shell and logs you	out. If	you are	using multiple windows,	this
       closes the active window.

   5.  The following command terminate all the processes that you own.	Sig-
       nals using this PID do not span cluster members.
	    kill -KILL -1

       This command sends SIGKILL to all the processes that you	own, even
       those that belong to other process groups.  If you are using multiple
       windows,	this command closes all	the windows.

   6.  The following command sends a specific signal to	a specific process:
	    kill -USR1 1103

       This command sends the SIGUSR1 signal to	process	1103.  The action
       taken on	the SIGUSR1 signal is defined by the particular	application
       you are running.

   7.  The following command lists the signal names in numerical order,
       stripped	of the SIG prefix:
	    kill -l

	     1)	HUP	      13) PIPE		25) XFSZ	  37) RTMIN+4
	     2)	INT	      14) ALRM		26) VTALRM	  38) RTMIN+5
	     3)	QUIT	      15) TERM		27) PROF	  39) RTMIN+6
	     4)	ILL	      16) URG		28) WINCH	  40) RTMIN+7
	     5)	TRAP	      17) STOP		29) PWR		  41) RTMAX-7
	     6)	LOST	      18) TSTP		30) USR1	  42) RTMAX-6
	     7)	EMT	      19) CONT		31) USR2	  43) RTMAX-5
	     8)	FPE	      20) CHLD		32) RESV	  44) RTMAX-4
	     9)	KILL	      21) TTIN		33) RTMIN	  45) RTMAX-3
	    10)	BUS	      22) TTOU		34) RTMIN+1	  46) RTMAX-2
	    11)	SEGV	      23) POLL		35) RTMIN+2	  47) RTMAX-1
	    12)	SYS	      24) XCPU		36) RTMIN+3	  48) RTMAX

       The command output can vary from	system to system.

ENVIRONMENT VARIABLES

  The following	environment variables affect the execution of kill:

  LANG
      Provides a default value for the internationalization variables that
      are unset	or null. If LANG is unset or null, the corresponding value
      from the default locale is used.	If any of the internationalization
      variables	contain	an invalid setting, the	utility	behaves	as if none of
      the variables had	been defined.

  LC_ALL
      If set to	a non-empty string value, overrides the	values of all the
      other internationalization variables.

  LC_CTYPE
      Determines the locale for	the interpretation of sequences	of bytes of
      text data	as characters (for example, single-byte	as opposed to multi-
      byte characters in arguments).

  LC_MESSAGES
      Determines the locale for	the format and contents	of diagnostic mes-
      sages written to standard	error.

  NLSPATH
      Determines the location of message catalogues for	the processing of
      LC_MESSAGES.

FILES

  <&lt;/usr/include/signal.h>&gt;
      Specifies	signal names.









SEE ALSO

  Commands:  csh(1), killall(8), ksh(1), ps(1),	Bourne shell sh(1b), POSIX
  shell	sh(1p)

  Functions:  kill(2), sigaction(2)

  Standards:  standards(5)