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32 .\" @(#)dmesg.8 8.1 (Berkeley) 6/5/93
33 .\" $FreeBSD: src/sbin/dmesg/dmesg.8,v 1.5.2.5 2002/08/21 18:58:17 trhodes Exp $
40 .Nd "display the system message buffer"
51 utility displays the contents of the system message buffer.
56 option is specified, the buffer is read from the currently running kernel
60 Otherwise, the buffer is read from the specified core file (or from the
61 default one), using the name list from the specified kernel image (or from
64 The options are as follows:
65 .Bl -tag -width indent
67 Show all data in the message buffer.
68 This includes any syslog records and
72 Clear the kernel buffer after printing.
74 After the initial message buffer dump
76 monitors the kernel for additional data and displays it as it arrives.
78 will not terminate until killed in this mode.
79 If this option is specified twice,
81 will live loop (use the cpu heavily) to obtain updates as quickly as
83 This second mode should only be used when trying to debug a kernel crashing
86 Extract values associated with the name list from the specified core
87 instead of the default
90 Extract the name list from the specified system instead of the default,
91 which is the kernel image the system has booted from.
94 .Bl -tag -width ".Pa /var/run/dmesg.boot" -compact
95 .It Pa /var/run/dmesg.boot
96 usually a snapshot of the buffer contents
97 taken soon after file systems are mounted