xref: /netbsd-src/sbin/dmesg/dmesg.8 (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1.\"	$NetBSD: dmesg.8,v 1.16 2004/04/30 16:11:03 wiz Exp $
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30.\"     @(#)dmesg.8	8.1 (Berkeley) 6/5/93
31.\"
32.Dd April 30, 2004
33.Dt DMESG 8
34.Os
35.Sh NAME
36.Nm dmesg
37.Nd "display the system message buffer"
38.Sh SYNOPSIS
39.Nm
40.Op Fl M Ar core
41.Op Fl N Ar system
42.Sh DESCRIPTION
43.Nm
44displays the contents of the system message buffer.
45.Pp
46The options are as follows:
47.Bl -tag -width Ds
48.It Fl M
49Extract values associated with the name list from the specified core
50instead of the default ``/dev/mem''.
51.It Fl N
52Extract the name list from the specified system instead of the default
53``/netbsd''.
54.El
55.Pp
56The system message buffer is a circular buffer of a fixed size.
57If the buffer has been filled, the first line of the
58.Nm
59output may not be complete.
60The size of the message buffer is configurable at compile-time on
61most systems with the
62.Dv MSGBUFSIZE
63kernel option.
64Look for
65.Dv MSGBUFSIZE
66in
67.Xr options 4
68for details.
69.Sh FILES
70.Bl -tag -width /var/run/dmesg.boot -compact
71.It Pa /var/run/dmesg.boot
72copy of dmesg at the time of last boot.
73.El
74.Sh SEE ALSO
75.Xr options 4 ,
76.Xr syslogd 8
77.Sh HISTORY
78The
79.Nm
80command appeared in
81.Bx 4.0 .
82