.\"	$NetBSD: dmesg.8,v 1.16 2004/04/30 16:11:03 wiz Exp $
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.\"     @(#)dmesg.8	8.1 (Berkeley) 6/5/93
.\"
.Dd April 30, 2004
.Dt DMESG 8
.Os
.Sh NAME
.Nm dmesg
.Nd "display the system message buffer"
.Sh SYNOPSIS
.Nm
.Op Fl M Ar core
.Op Fl N Ar system
.Sh DESCRIPTION
.Nm
displays the contents of the system message buffer.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl M
Extract values associated with the name list from the specified core
instead of the default ``/dev/mem''.
.It Fl N
Extract the name list from the specified system instead of the default
``/netbsd''.
.El
.Pp
The system message buffer is a circular buffer of a fixed size.
If the buffer has been filled, the first line of the
.Nm
output may not be complete.
The size of the message buffer is configurable at compile-time on
most systems with the
.Dv MSGBUFSIZE
kernel option.
Look for
.Dv MSGBUFSIZE
in
.Xr options 4
for details.
.Sh FILES
.Bl -tag -width /var/run/dmesg.boot -compact
.It Pa /var/run/dmesg.boot
copy of dmesg at the time of last boot.
.El
.Sh SEE ALSO
.Xr options 4 ,
.Xr syslogd 8
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.0 .