[apple/xnu.git] / bsd / man / man5 / core.5

.\""Copyright (c) 2001 Apple Computer, Inc. All Rights Reserved.
.\"The contents of this file constitute Original Code as defined in and are 
.\"subject to the Apple Public Source License Version 1.2 (the 'License'). 
.\"You may not use this file except in compliance with the
.\"License. Please obtain a copy of the License at 
.\"http://www.apple.com/publicsource and read it before using this file.
.\"
.\"This Original Code and all software distributed under the License are
.\"distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
.\"EXPRESS OR IMPLIED, AND APPLE
.\"HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY 
.\"WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
.\"QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the 
.\"specific language governing rights and limitations under the License."
.Dd March 18, 2002
.Dt CORE 5
.Os
.Sh NAME
.Nm core
.Nd memory image file format
.Sh SYNOPSIS
.In sys/param.h
.Sh DESCRIPTION
A small number of signals which cause abnormal termination of a process
also cause a record of the process's in-core state to be written
to disk for later examination by one of the available debuggers.
(See
.Xr sigaction 2 . )
This memory image is written to a file named by default
.Pa core.pid ,
where
.Va pid
is the process ID of the process,
in the
.Pa /cores
directory,
provided the terminated process had write permission in the directory,
and the directory existed.
.Pp
The maximum size of a core file is limited by
.Xr setrlimit 2 .
Files which would be larger than the limit are not created.
.Pp
The core file consists of the
.Xr Mach-O 5
header as  described in the
.Aq Pa mach-o/loader.h
file.
The remainder of the core
file consists of various sections described in the
.Xr Mach-O 5
header.
.Sh NOTE
Core dumps are disabled by default under Darwin/Mac OS X.  To re-enable 
core dumps, a privileged user must edit
.Pa /etc/hostconfig
to contain the line:
.Bd -literal
COREDUMPS=-YES-
.Ed
.Sh SEE ALSO
.Xr gdb 1 ,
.Xr setrlimit 2 ,
.Xr sigaction 2 ,
.Xr Mach-O 5 ,
.Xr sysctl 8
.Sh HISTORY
A
.Nm
file format appeared in
.At v6 .
Commit	Line	Data
9bccf70c A	1	.\""Copyright (c) 2001 Apple Computer, Inc. All Rights Reserved.
	2	.\"The contents of this file constitute Original Code as defined in and are
	3	.\"subject to the Apple Public Source License Version 1.2 (the 'License').
	4	.\"You may not use this file except in compliance with the
	5	.\"License. Please obtain a copy of the License at
	6	.\"http://www.apple.com/publicsource and read it before using this file.
	7	.\"
	8	.\"This Original Code and all software distributed under the License are
	9	.\"distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	10	.\"EXPRESS OR IMPLIED, AND APPLE
	11	.\"HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY
	12	.\"WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
	13	.\"QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
	14	.\"specific language governing rights and limitations under the License."
	15	.Dd March 18, 2002
	16	.Dt CORE 5
	17	.Os
	18	.Sh NAME
	19	.Nm core
	20	.Nd memory image file format
	21	.Sh SYNOPSIS
	22	.In sys/param.h
	23	.Sh DESCRIPTION
	24	A small number of signals which cause abnormal termination of a process
	25	also cause a record of the process's in-core state to be written
	26	to disk for later examination by one of the available debuggers.
	27	(See
	28	.Xr sigaction 2 . )
	29	This memory image is written to a file named by default
2d21ac55 A	30	.Pa core.pid ,
	31	where
	32	.Va pid
	33	is the process ID of the process,
9bccf70c	34	in the
2d21ac55 A	35	.Pa /cores
2d21ac55 A	36	directory,
9bccf70c A	37	provided the terminated process had write permission in the directory,
	38	and the directory existed.
	39	.Pp
	40	The maximum size of a core file is limited by
	41	.Xr setrlimit 2 .
	42	Files which would be larger than the limit are not created.
	43	.Pp
	44	The core file consists of the
2d21ac55	45	.Xr Mach-O 5
9bccf70c	46	header as described in the
55e303ae	47	.Aq Pa mach-o/loader.h
9bccf70c A	48	file.
	49	The remainder of the core
	50	file consists of various sections described in the
	51	.Xr Mach-O 5
	52	header.
55e303ae	53	.Sh NOTE
2d21ac55 A	54	Core dumps are disabled by default under Darwin/Mac OS X. To re-enable
2d21ac55 A	55	core dumps, a privileged user must edit
55e303ae A	56	.Pa /etc/hostconfig
	57	to contain the line:
	58	.Bd -literal
	59	COREDUMPS=-YES-
	60	.Ed
9bccf70c A	61	.Sh SEE ALSO
	62	.Xr gdb 1 ,
	63	.Xr setrlimit 2 ,
	64	.Xr sigaction 2 ,
55e303ae	65	.Xr Mach-O 5 ,
9bccf70c A	66	.Xr sysctl 8
	67	.Sh HISTORY
	68	A
	69	.Nm
	70	file format appeared in
	71	.At v6 .