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KILL(1)				 User Commands			       KILL(1)



NAME
       kill - terminate a process

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

DESCRIPTION
       The command kill sends the specified signal to the specified process or
       process group.  If no signal is specified, the  TERM  signal  is	 sent.
       The  TERM  signal  will	kill processes which do not catch this signal.
       For other processes, it may be necessary to use the  KILL  (9)  signal,
       since this signal cannot be caught.

       Most  modern  shells  have a builtin kill function, with a usage rather
       similar to that of the command  described  here.	  The  '-a'  and  '-p'
       options, and the possibility to specify processes by command name are a
       local extension.

       If sig is 0, then no signal is sent, but error checking is  still  per-
       formed.

OPTIONS
       pid... Specify the list of processes that kill should signal.  Each pid
	      can be one of five things:

	      n	     where n is larger than 0.	The process with pid n will be
		     signaled.

	      0	     All processes in the current process group are signaled.

	      -1     All processes with pid larger than 1 will be signaled.

	      -n     where n is larger than 1.	All processes in process group
		     n are signaled.  When an argument of  the	form  '-n'  is
		     given,  and it is meant to denote a process group, either
		     the signal must be specified first, or the argument  must
		     be	 preceded by a '--' option, otherwise it will be taken
		     as the signal to send.

	      commandname
		     All processes invoked using that name will be signaled.

       -s, --signal signal
	      Specify the signal to send.  The signal may be given as a signal
	      name or number.

       -l, --list [signal]
	      Print  a	list of signal names, or convert signal given as argu-
	      ment to a name.  The signals are	found  in  /usr/include/linux/
	      signal.h

       -L, --table
	      Similar to -l, but will print signal names and their correspond-
	      ing numbers.

       -a, --all
	      Do not restrict the commandname-to-pid conversion	 to  processes
	      with the same uid as the present process.

       -p, --pid
	      Specify  that kill should only print the process id (pid) of the
	      named processes, and not send any signals.

       -q, --queue sigval
	      Use sigqueue(2) rather than kill(2) and the sigval  argument  is
	      used  to	specify an integer to be sent with the signal.	If the
	      receiving process has installed a handler for this signal	 using
	      the  SA_SIGINFO  flag  to	 sigaction(2), then it can obtain this
	      data via the si_value field of the siginfo_t structure.

NOTES
       It is not possible to send a signal to explicitly selected thread in  a
       multithreaded process by kill(2) syscall.  If kill(2) is used to send a
       signal to a thread group, then kernel selects arbitrary member  of  the
       thread  group  that  has	 not blocked the signal.  For more details see
       clone(2) CLONE_THREAD description.

       The command kill(1) as well as syscall kill(2) accepts TID (thread  ID,
       see  gettid(2))	as  argument.	In  this case the kill behavior is not
       changed and the signal is also delivered to  the	 thread	 group	rather
       than to the specified thread.

SEE ALSO
       bash(1), tcsh(1), kill(2), sigvec(2), signal(7)

AUTHOR
       Taken  from BSD 4.4.  The ability to translate process names to process
       ids was added by Salvatore Valente <svalente@mit.edu>.

AVAILABILITY
       The kill command is part of the util-linux  package  and	 is  available
       from  Linux  Kernel Archive <ftp://ftp.kernel.org/pub/linux/utils/util-
       linux/>.



util-linux			  March 2013			       KILL(1)