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kill(1) [centos man page]

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 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)

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KILL(1)                                                            User Commands                                                           KILL(1)

NAME
kill - send a signal to a process SYNOPSIS
kill [options] <pid> [...] 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 or -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. OPTIONS
<pid> [...] Send signal to every <pid> listed. -<signal> -s <signal> --signal <signal> Specify the signal to be sent. The signal can be specified by using name or number. The behavior of signals is explained in sig- nal(7) manual page. -l, --list [signal] List signal names. This option has optional argument, which will convert signal number to signal name, or other way round. -L, --table List signal names in a nice table. 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. SEE ALSO
kill(2), killall(1), nice(1), pkill(1), renice(1), signal(7), skill(1) 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. REPORTING BUGS
Please send bug reports to <procps@freelists.org> procps-ng October 2011 KILL(1)

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