freebsd-skq/sbin/dmesg/dmesg.8

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.\"     @(#)dmesg.8	8.1 (Berkeley) 6/5/93
.\" $FreeBSD$
.\"
.Dd June 5, 1993
.Dt DMESG 8
.Os BSD 4
.Sh NAME
.Nm dmesg
.Nd "display the system message buffer"
.Sh SYNOPSIS
.Nm
.Op Fl a
.Op Fl M Ar core
.Op Fl N Ar system
.Sh DESCRIPTION
.Nm Dmesg
displays the contents of the system message buffer.
If neither the
.Fl N
nor the
.Fl M
option is specified, the buffer is read from the currently running kernel
via the
.Xr sysctl 3
interface.
Otherwise, the buffer is read from the specified core file (or from the
default one), using the name list from the specified kernel image (or from
the default image).
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl a
Show all data in the message buffer.
This includes any syslog records and
.Pa /dev/console
output.
.It Fl M
Extract values associated with the name list from the specified core
instead of the default
.Pa /dev/kmem .
.It Fl N
Extract the name list from the specified system instead of the default,
which is the kernel image the system has booted from.
.El
.Sh SEE ALSO
.Xr sysctl 3 ,
.Xr syslogd 8
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.0 .