1.\" $NetBSD: crash.8,v 1.8 2019/03/23 02:07:32 mrg Exp $ 2.\" 3.\" Copyright (c) 2009 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Andrew Doran. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd March 22, 2019 31.Dt CRASH 8 32.Os 33.Sh NAME 34.Nm crash 35.Nd examine and debug system images 36.Sh SYNOPSIS 37.Nm 38.Op Fl w 39.Op Fl M Ar core 40.Op Fl N Ar kernel 41.Sh DESCRIPTION 42The 43.Nm 44command is used to examine and debug system images. 45.Pp 46If run without any arguments, 47.Nm 48operates on the running system. 49.Pp 50The options are as follows: 51.Bl -tag -width xpalidocious 52.It Fl M Ar core 53Operate on the specified crash dump instead of the default 54.Pa /dev/mem . 55Crash dumps should be from the same version of the system and same machine 56architecture as the running version of 57.Nm crash , 58and must be uncompressed. 59.It Fl N Ar kernel 60Extract the name list from the specified kernel instead of the default 61.Pa /dev/ksyms . 62.It Fl w 63Enable writing. 64.El 65.Pp 66The command syntax used by 67.Nm 68is the same as the in-kernel debugger. 69See the 70.Xr ddb 4 71manual page for more information. 72.Pp 73Operations and facilities that require a running system, such as breakpoints, 74are not supported by 75.Nm crash . 76.Pp 77.Nm 78does not provide pagination. 79However, by using the pipe symbol, output may be sent to commands available 80from the shell. 81For example: 82.Bd -literal -offset abcd 83crash> ps | more 84crash> ps | grep ioflush 85.Ed 86.Sh EXAMPLES 87You can obtain a full list of all kernel stack traces with a shell pipeline 88like the following: 89.Bd -literal -offset abcd 90# echo ps | crash | grep '^[0-9]' | cut -c 30-46 | \\ 91 sed 's,^,bt/a ,' | crash 92.Ed 93.Sh SEE ALSO 94.Xr ps 1 , 95.Xr vmstat 1 , 96.Xr ddb 4 , 97.Xr pstat 8 98.Sh HISTORY 99The 100.Nm 101command appeared in 102.Nx 6.0 . 103.Sh BUGS 104The 105.Nm 106command for the sparc port is unstable. 107