1.\" $OpenBSD: kdump.1,v 1.40 2023/12/15 15:12:08 deraadt Exp $ 2.\" 3.\" Copyright (c) 1990, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" from: @(#)kdump.1 8.1 (Berkeley) 6/6/93 31.\" 32.Dd $Mdocdate: December 15 2023 $ 33.Dt KDUMP 1 34.Os 35.Sh NAME 36.Nm kdump 37.Nd display kernel trace data 38.Sh SYNOPSIS 39.Nm kdump 40.Op Fl dHlnRTXx 41.Op Fl f Ar file 42.Op Fl m Ar maxdata 43.Op Fl P Ar program 44.Op Fl p Ar pid 45.Op Fl t Ar trstr 46.Op Fl u Ar label 47.Sh DESCRIPTION 48.Nm 49displays the kernel trace files produced with 50.Xr ktrace 1 51in human-readable format. 52By default, the file 53.Pa ktrace.out 54in the current directory is displayed, unless overridden by the 55.Fl f 56option. 57.Pp 58The options are as follows: 59.Bl -tag -width Ds 60.It Fl d 61Display all numbers in decimal. 62By default, values are printed out in hexadecimal. 63.It Fl f Ar file 64Display the specified file instead of 65.Pa ktrace.out . 66Specifying 67.Sq - 68will read from standard input. 69.It Fl H 70Display thread identifiers. 71.It Fl l 72Loop reading the trace file, once the end-of-file is reached, waiting for 73more data. 74.It Fl m Ar maxdata 75Display at most 76.Ar maxdata 77bytes when decoding I/O. 78.It Fl n 79Suppress ad hoc translations. 80Normally 81.Nm 82tries to decode many system calls into a more human-readable format. 83For example, 84.Xr ioctl 2 85values are replaced with the macro name and 86.Va errno 87values are replaced with the 88.Xr strerror 3 89string. 90Suppressing this feature yields a more consistent output format and is 91easily amenable to further processing. 92.It Fl P Ar program 93Show output only for processes with 94.Ar program 95as their command name. 96.It Fl p Ar pid 97Show output only for the 98.Ar pid 99specified. 100.It Fl R 101Display relative timestamps (time since previous entry). 102.It Fl T 103Display absolute timestamps for each entry (seconds since the Epoch). 104.It Fl TR 105If both options are specified, display timestamps relative to trace start. 106.It Fl t Ar trstr 107Select which tracepoints to display. 108The argument can contain one or more of the following letters. 109By default all trace points except for 110.Cm X 111are enabled. 112.Pp 113.Bl -tag -width flag -offset indent -compact 114.\" Keep this list in sync with ktrace(1) and ltrace(1). 115.It Cm c 116trace system calls 117.It Cm i 118trace I/O 119.It Cm n 120trace namei translations 121.It Cm p 122trace violation of 123.Xr pledge 2 124restrictions 125.It Cm s 126trace signal processing 127.It Cm S 128trace violation of 129.Xr pinsyscalls 2 130.It Cm t 131trace various structures 132.It Cm u 133trace user data coming from 134.Xr utrace 2 135.It Cm x 136trace argument vector in 137.Xr execve 2 138.It Cm X 139trace environment in 140.Xr execve 2 141.It Cm + 142trace the default points 143.El 144.It Fl u Ar label 145Display 146.Xr utrace 2 147tracepoints having 148.Xr utrace 2 149label 150.Ar label 151as strings with 152.Xr vis 3 153escaping, without 154.Xr ktrace 2 155header information. 156.It Fl X 157Display I/O data with hexadecimal data and printable ASCII characters 158side by side. 159.It Fl x 160Display I/O data in hexadecimal. 161.El 162.Pp 163The 164.Fl t 165and 166.Fl u 167options are mutually exclusive; 168the last one specified overrides any previous ones. 169.Sh FILES 170.Bl -tag -width ktrace.out -compact 171.It Pa ktrace.out 172default ktrace dump file 173.El 174.Sh SEE ALSO 175.Xr ktrace 1 176.Sh HISTORY 177The 178.Nm 179command appeared in 180.Bx 4.3 Reno . 181