1.\"	$OpenBSD: kill.1,v 1.26 2004/07/06 13:32:44 jmc Exp $
2.\"	$NetBSD: kill.1,v 1.8 1995/09/07 06:30:26 jtc Exp $
3.\"
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34.\"	@(#)kill.1	8.2 (Berkeley) 4/28/95
35.\"
36.Dd $Mdocdate: February 11 2011 $
37.Dt KILL 1
38.Os
39.Sh NAME
40.Nm kill
41.Nd terminate or signal a process
42.Sh SYNOPSIS
43.Nm kill
44.Op Fl s Ar signal_name
45.Ar pid
46.Op Ar ...
47.Nm kill
48.Fl l
49.Op Ar exit_status
50.Nm kill
51.Fl Ar signal_name
52.Ar pid
53.Op Ar ...
54.Nm kill
55.Fl Ar signal_number
56.Ar pid
57.Op Ar ...
58.Sh DESCRIPTION
59The
60.Nm
61utility sends a signal to the process(es) specified
62by the
63.Ar pid
64operand(s).
65If no signal is specified,
66.Dv SIGTERM
67is used.
68.Pp
69Only the superuser may send signals to other users' processes.
70.Pp
71The options are as follows:
72.Bl -tag -width Ds
73.It Fl s Ar signal_name
74A symbolic signal name specifying the signal to be sent instead of the
75default
76.Dv SIGTERM .
77.It Fl l Op Ar exit_status
78If no operand is given, list the signal names; otherwise, write
79the signal name corresponding to
80.Ar exit_status .
81.It Fl Ar signal_name
82A symbolic signal name specifying the signal to be sent instead of the
83default
84.Dv SIGTERM .
85.It Fl Ar signal_number
86A non-negative decimal integer specifying the signal to be sent instead
87of the default
88.Dv SIGTERM .
89.El
90.Pp
91The following PIDs have special meanings:
92.Bl -tag -width Ds -offset indent
93.It \-1
94If superuser, broadcast the signal to all processes; otherwise, broadcast
95to all processes belonging to the user.
96.It \- Ns Ar pgid
97Send the signal to all processes within the specified process group.
98.El
99.Pp
100Some of the more commonly used signals:
101.Pp
102.Bl -tag -width Ds -compact -offset indent
103.It 1
104HUP (hang up)
105.It 2
106INT (interrupt)
107.It 3
108QUIT (quit)
109.It 6
110ABRT (abort)
111.It 9
112KILL (non-catchable, non-ignorable kill)
113.It 14
114ALRM (alarm clock)
115.It 15
116TERM (software termination signal)
117.El
118.Pp
119For a more complete list, consult the
120.Xr sigaction 2
121manual page.
122.Pp
123A signal number of 0
124.Pq Li kill \-0 pid
125checks the validity of a certain PID, to see if it exists.
126An exit code of 0 means that the specified process exists.
127.Pp
128The
129.Nm
130utility exists as a built-in to most shells;
131they allow job specifiers of the form
132.Dq %...
133as arguments,
134so process IDs are not as often used as
135.Nm
136arguments.
137.Sh EXAMPLES
138Forcibly terminate process ID 1234:
139.Pp
140.Dl $ kill -9 1234
141.Pp
142Send the
143.Xr inetd 8
144daemon the hangup signal, instructing it to re-read its configuration from
145.Pa /etc/inetd.conf :
146.Pp
147.Dl $ sudo kill -HUP $(cat /var/run/inetd.pid)
148.Sh SEE ALSO
149.Xr csh 1 ,
150.Xr pkill 1 ,
151.Xr ps 1 ,
152.Xr sh 1 ,
153.Xr kill 2 ,
154.Xr sigaction 2
155.Sh STANDARDS
156The
157.Nm
158utility is expected to be
159.St -p1003.2
160compatible.
161.Sh HISTORY
162A
163.Nm
164command appeared in
165.At v3 .
166It is actually an
167.Nm mksh
168builtin in
169.Mx 11 .
170