freebsd/usr.sbin/nvram/nvram.8

.\"-
.\" Copyright (c) 2006 Maxim Sobolev <sobomax@FreeBSD.org>
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.Dd June 19, 2020
.Dt NVRAM 8 powerpc
.Os
.Sh NAME
.Nm nvram
.Nd "display or modify contents of the EEPROM or NVRAM"
.Sh SYNOPSIS
.Nm
.Fl p
.Nm
.Oo Fl d Ar name Oc Ar ...
.Op Ar name Ns = Ns Ar value ...
.Sh DESCRIPTION
The
.Nm
utility provides an interface for displaying and changing the system's
configuration variables contained in EEPROM or NVRAM.
In the first synopsis form, all available configuration variables and their
current values are printed.
In the second form, the variable selected by
.Ar name
is either removed or its value is changed to the
.Ar value
following by
.Ql =
sign.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl d Ar name
Delete the variable selected by
.Ar name
from the EEPROM or NVRAM.
The
.Fl d
flag can be specified multiple times, in which case multiple variables
will be removed.
.It Fl p
Print all available configuration variables and their current values.
.El
.Sh EXAMPLES
Print all available configuration variables and their current values:
.Pp
.Dl "nvram -p"
.Pp
Remove the variable named
.Va local-mac-address? :
.Pp
.Dl "nvram -d local-mac-address\e?"
.Pp
Set the value of the
.Va local-mac-address?
variable to
.Dq Li true :
.Pp
.Dl "nvram local-mac-address\e?=true"
.Pp
Note that the
.Ql \e
in the above examples is used to keep the shell from interpreting the
.Ql \&? .
.Pp
Remove variables named
.Va foo
and
.Va bar
and set variable named
.Va baz
to
.Dq Li 100 :
.Pp
.Dl "nvram -d foo -d bar baz=100"
.Sh SEE ALSO
.Xr powermac_nvram 4
.Sh HISTORY
The
.Nm
utility first appeared in
.Fx 7.0 .
It is inspired by the
Darwin/Mac OS X
.Nm
utility.
.Sh AUTHORS
.An Maxim Sobolev Aq Mt sobomax@FreeBSD.org