.\""Copyright (c) 2001-2007 Apple 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 June 26, 2008 .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 do one of the following .Pp * Edit .Pa /etc/launchd.conf or .Pa $HOME/.launchd.conf and add a line specifying the limit .Pa limit core unlimited .Pp * A privileged user can also enable cores with .Pa launchctl limit core unlimited .Pp * A privileged user can also enable core files by using .Xr ulimit 1 or .Xr limit 1 depending upon the shell. .Sh SEE ALSO .Xr gdb 1 , .Xr setrlimit 2 , .Xr sigaction 2 , .Xr Mach-O 5 , .Xr launchd.conf 5 , .Xr launchd.plist 5 , .Xr sysctl 8 .Sh HISTORY A .Nm file format appeared in .At v6 .