misc-utils/kill.1

   1 .\" Copyright 1994 Salvatore Valente (svalente@mit.edu)
   2 .\" Copyright 1992 Rickard E. Faith (faith@cs.unc.edu)
   3 .\" May be distributed under the GNU General Public License
   4 .TH KILL 1 "March 2013" "util-linux" "User Commands"
   5 .SH NAME
   6 kill \- terminate a process
   7 .SH SYNOPSIS
   8 .B kill
   9 .RB [ \-s
  10 .IR signal  | \fB\-p\fP ]
  11 .RB [ \-q
  12 .IR sigval ]
  13 .RB [ \-a ]
  14 .RB [ \-\- ]
  15 .IR pid ...
  16 .br
  17 .B kill -l
  18 .RI [ signal ]
  19 .SH DESCRIPTION
  20 The command
  21 .B kill
  22 sends the specified signal to the specified process or process group.  If no
  23 signal is specified, the TERM signal is sent.  The TERM signal will kill
  24 processes which do not catch this signal.  For other processes, it may be
  25 necessary to use the KILL (9) signal, since this signal cannot be caught.
  26 .PP
  27 Most modern shells have a builtin kill function, with a usage rather similar to
  28 that of the command described here.  The '-a' and '-p' options, and the
  29 possibility to specify processes by command name are a local extension.
  30 .PP
  31 If sig is 0, then no signal is sent, but error checking is still performed.
  32 .SH OPTIONS
  33 .TP
  34 .IR pid ...
  35 Specify the list of processes that
  36 .B kill
  37 should signal.  Each
  38 .I pid
  39 can be one of five things:
  40 .RS
  41 .TP
  42 .I n
  43 where
  44 .I n
  45 is larger than 0.  The process with pid
  46 .I n
  47 will be signaled.
  48 .TP
  49 .B 0
  50 All processes in the current process group are signaled.
  51 .TP
  52 .B -1
  53 All processes with pid larger than 1 will be signaled.
  54 .TP
  55 .BI - n
  56 where
  57 .I n
  58 is larger than 1.  All processes in process group
  59 .I n
  60 are signaled.  When an argument of the form '-n' is given, and it is meant to
  61 denote a process group, either the signal must be specified first, or the
  62 argument must be preceded by a '--' option, otherwise it will be taken as the
  63 signal to send.
  64 .TP
  65 .I commandname
  66 All processes invoked using that name will be signaled.
  67 .RE
  68 .TP
  69 \fB\-s\fR, \fB\-\-signal\fR \fIsignal\fR
  70 Specify the signal to send.  The signal may be given as a signal name or
  71 number.
  72 .TP
  73 \fB\-l\fR, \fB\-\-list\fR [\fIsignal\fR]
  74 Print a list of signal names, or convert signal given as argument to a name.
  75 The signals are found in
  76 .I /usr/\:include/\:linux/\:signal.h
  77 .TP
  78 \fB\-L\fR, \fB\-\-table\fR
  79 Similar to \-l, but will print signal names and their corresponding
  80 numbers.
  81 .TP
  82 \fB\-a\fR, \fB\-\-all\fR
  83 Do not restrict the commandname-to-pid conversion to processes with the same
  84 uid as the present process.
  85 .TP
  86 \fB\-p\fR, \fB\-\-pid\fR
  87 Specify that
  88 .B kill
  89 should only print the process id (pid) of the named processes, and not send any
  90 signals.
  91 .IP
  92 The \-\-pid option functionality is also enabled when the command
  93 copied or linked to name
  94 .BR pid .
  95 This functionality is deprecated, and will not be removed in March 2016.
  96 .TP
  97 \fB\-q\fR, \fB\-\-queue\fR \fIsigval\fR
  98 Use
  99 .BR sigqueue (2)
 100 rather than
 101 .BR kill (2)
 102 and the
 103 .I sigval
 104 argument is used to specify an integer to be sent with the signal.  If the
 105 receiving process has installed a handler for this signal using the SA_SIGINFO
 106 flag to
 107 .BR sigaction (2),
 108 then it can obtain this data via the si_value field of the siginfo_t structure.
 109 .SH NOTES
 110 It is not possible to send a signal to explicitly selected thread in a
 111 multithreaded process by
 112 .BR kill (2)
 113 syscall.  If
 114 .BR kill(2)
 115 is used to send a signal to a thread group, then kernel selects arbitrary
 116 member of the thread group that has not blocked the signal.  For more details
 117 see
 118 .BR clone (2)
 119 CLONE_THREAD description.
 120 .PP
 121 The command
 122 .BR kill (1)
 123 as well as syscall
 124 .BR kill (2)
 125 accepts TID (thread ID, see
 126 .BR gettid (2))
 127 as argument.  In this case the kill behavior is not changed and the signal is
 128 also delivered to the thread group rather than to the specified thread.
 129 .SH "SEE ALSO"
 130 .BR bash (1),
 131 .BR tcsh (1),
 132 .BR kill (2),
 133 .BR sigvec (2),
 134 .BR signal (7)
 135 .SH AUTHOR
 136 Taken from BSD 4.4.  The ability to translate process names to process ids was
 137 added by
 138 .MT svalente@mit.edu
 139 Salvatore Valente
 140 .ME .
 141 .SH AVAILABILITY
 142 The kill command is part of the util-linux package and is available from
 143 .UR ftp://\:ftp.kernel.org\:/pub\:/linux\:/utils\:/util-linux/
 144 Linux Kernel Archive
 145 .UE .