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.\" $Id: core.5,v 1.5 1997/02/22 13:25:57 peter Exp $ 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 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 59.Nm programname.core 60file is limited by 61.Xr setrlimit 2 . 62Files which would be larger than the limit are not created. 63.Pp 64The 65.Nm programname.core 66file consists of the 67.Fa u . 68area, whose size (in pages) is 69defined by the 70.Dv UPAGES 71manifest in the 72.Aq Pa sys/param.h 73file. The 74.Fa u . 75area starts with a 76.Fa user 77structure as given in 78.Aq Pa sys/user.h . 79The remainder of the 80.Nm programname.core 81file consists of the data pages followed by 82the stack pages of the process image. 83The amount of data space image in the 84.Nm programname.core 85file is given (in pages) by the 86variable 87.Fa u_dsize 88in the 89.Fa u . 90area. 91The amount of stack image in the core file is given (in pages) by the 92variable 93.Fa u_ssize 94in the 95.Ar u . 96area. 97The size of a ``page'' is given by the constant 98.Dv PAGE_SIZE 99(also from 100.Aq Pa sys/param.h ) . 101.Sh SEE ALSO 102.Xr gdb 1 , 103.Xr kgdb 1 , 104.Xr setrlimit 2 , 105.Xr sigaction 2 106.Sh HISTORY 107A 108.Nm core 109file format appeared in 110.At v6 . 111