1.\" Copyright (c) 1980, 1991, 1993
2.\" The Regents of the University of California. All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\" notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\" notice, this list of conditions and the following disclaimer in the
11.\" documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\" must display the following acknowledgement:
14.\" This product includes software developed by the University of
15.\" California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" @(#)core.5 8.3 (Berkeley) 12/11/93
33.\" $FreeBSD: head/share/man/man5/core.5 68962 2000-11-20 18:41:33Z ru $
34.\"
35.Dd December 11, 1993
36.Dt CORE 5
37.Os BSD 4
38.Sh NAME
39.Nm core
40.Nd memory image file format
41.Sh SYNOPSIS
42.Fd #include <sys/param.h>
43.Sh DESCRIPTION
44A small number of signals which cause abnormal termination of a process
45also cause a record of the process's in-core state to be written
46to disk for later examination by one of the available debuggers.
47(See
48.Xr sigaction 2 . )
49This memory image is written to a file named by default
50.Nm programname.core
51in the working directory;
52provided the terminated process had write permission in the directory,
53and provided the abnormality did not cause
54a system crash.
55(In this event, the decision to save the core file is arbitrary, see
56.Xr savecore 8 . )
57.Pp
58The maximum size of a core file is limited by
59.Xr setrlimit 2 .
60Files which would be larger than the limit are not created.
61.Pp
62The name of the file is controlled via the
63.Xr sysctl 8
64variable
65.Va kern.corefile .
66The contents of this variable describes a filename to store
67the core image to. This filename can be absolute, or relative (which
68will resolve to the current working directory of the program
69generating it). Any sequence of
70.Em \&%N
71in this filename template will be replaced by the process name,
72.Em \&%P
73by the processes PID, and
74.Em \&%U
75by the UID. The name defaults to
76.Em \&%N.core ,
77yielding the traditional
78.Fx
79behaviour.
80.Pp
81The core file consists of the
82.Fa u .
83area, whose size (in pages) is
84defined by the
85.Dv UPAGES
86manifest in the
87.Aq Pa sys/param.h
88file. The
89.Fa u .
90area starts with a
91.Fa user
92structure as given in
93.Aq Pa sys/user.h .
94The remainder of the core
95file consists of the data pages followed by
96the stack pages of the process image.
97The amount of data space image in the core
98file is given (in pages) by the
99variable
100.Fa u_dsize
101in the
102.Fa u .
103area.
104The amount of stack image in the core file is given (in pages) by the
105variable
106.Fa u_ssize
107in the
108.Ar u .
109area.
110The size of a ``page'' is given by the constant
111.Dv PAGE_SIZE
112(also from
113.Aq Pa sys/param.h ) .
114.Sh EXAMPLES
115In order to store all core images in per-user private areas under
116.Pa /var/coredumps ,
117the following
118.Xr sysctl 8
119command can be used:
120.Pp
121.Dl sysctl -w kern.corefile="/var/coredumps/\&%U/\&%N.core"
122.Sh SEE ALSO
123.Xr gdb 1 ,
124.Xr kgdb 1 ,
125.Xr setrlimit 2 ,
126.Xr sigaction 2 ,
127.Xr sysctl 8
128.Sh HISTORY
129A
130.Nm
131file format appeared in
132.At v6 .
2.\" The Regents of the University of California. All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\" notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\" notice, this list of conditions and the following disclaimer in the
11.\" documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\" must display the following acknowledgement:
14.\" This product includes software developed by the University of
15.\" California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" @(#)core.5 8.3 (Berkeley) 12/11/93
33.\" $FreeBSD: head/share/man/man5/core.5 68962 2000-11-20 18:41:33Z ru $
34.\"
35.Dd December 11, 1993
36.Dt CORE 5
37.Os BSD 4
38.Sh NAME
39.Nm core
40.Nd memory image file format
41.Sh SYNOPSIS
42.Fd #include <sys/param.h>
43.Sh DESCRIPTION
44A small number of signals which cause abnormal termination of a process
45also cause a record of the process's in-core state to be written
46to disk for later examination by one of the available debuggers.
47(See
48.Xr sigaction 2 . )
49This memory image is written to a file named by default
50.Nm programname.core
51in the working directory;
52provided the terminated process had write permission in the directory,
53and provided the abnormality did not cause
54a system crash.
55(In this event, the decision to save the core file is arbitrary, see
56.Xr savecore 8 . )
57.Pp
58The maximum size of a core file is limited by
59.Xr setrlimit 2 .
60Files which would be larger than the limit are not created.
61.Pp
62The name of the file is controlled via the
63.Xr sysctl 8
64variable
65.Va kern.corefile .
66The contents of this variable describes a filename to store
67the core image to. This filename can be absolute, or relative (which
68will resolve to the current working directory of the program
69generating it). Any sequence of
70.Em \&%N
71in this filename template will be replaced by the process name,
72.Em \&%P
73by the processes PID, and
74.Em \&%U
75by the UID. The name defaults to
76.Em \&%N.core ,
77yielding the traditional
78.Fx
79behaviour.
80.Pp
81The core file consists of the
82.Fa u .
83area, whose size (in pages) is
84defined by the
85.Dv UPAGES
86manifest in the
87.Aq Pa sys/param.h
88file. The
89.Fa u .
90area starts with a
91.Fa user
92structure as given in
93.Aq Pa sys/user.h .
94The remainder of the core
95file consists of the data pages followed by
96the stack pages of the process image.
97The amount of data space image in the core
98file is given (in pages) by the
99variable
100.Fa u_dsize
101in the
102.Fa u .
103area.
104The amount of stack image in the core file is given (in pages) by the
105variable
106.Fa u_ssize
107in the
108.Ar u .
109area.
110The size of a ``page'' is given by the constant
111.Dv PAGE_SIZE
112(also from
113.Aq Pa sys/param.h ) .
114.Sh EXAMPLES
115In order to store all core images in per-user private areas under
116.Pa /var/coredumps ,
117the following
118.Xr sysctl 8
119command can be used:
120.Pp
121.Dl sysctl -w kern.corefile="/var/coredumps/\&%U/\&%N.core"
122.Sh SEE ALSO
123.Xr gdb 1 ,
124.Xr kgdb 1 ,
125.Xr setrlimit 2 ,
126.Xr sigaction 2 ,
127.Xr sysctl 8
128.Sh HISTORY
129A
130.Nm
131file format appeared in
132.At v6 .