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 performed.

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 argument 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 corresponding 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 han-
              dler 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)