.\"-
.\" Copyright (c) 2000  Peter Wemm <peter@FreeBSD.org>
.\"
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.Dd May 11, 2012
.Dt KENV 1
.Os
.Sh NAME
.Nm kenv
.Nd dump or modify the kernel environment
.Sh SYNOPSIS
.Nm
.Op Fl hNq
.Nm
.Op Fl qv
.Ar variable Ns Op = Ns Ar value
.Nm
.Op Fl q
.Fl u
.Ar variable
.Sh DESCRIPTION
The
.Nm
utility will dump the kernel environment if
invoked without arguments.
If the
.Fl h
option is specified, it will limit the report to kernel probe hints.
If an optional
.Ar variable
name is specified,
.Nm
will only report that value.
If the
.Fl N
option is specified,
.Nm
will only display variable names and not their values.
If the
.Fl u
option is specified,
.Nm
will delete the given environment variable.
If the environment variable is followed by an optional
.Ar value ,
.Nm
will set the environment variable to this value.
.Pp
If the
.Fl q
option is set, warnings normally printed as a result of being unable to
perform the requested operation will be suppressed.
.Pp
If the
.Fl v
option is set, the variable name will be printed out for the
environment variable in addition to the value when
.Nm
is executed with a variable name.
.Pp
Variables can be added to the kernel environment using the
.Pa /boot/loader.conf
file, or also statically compiled into the kernel using the statement
.Pp
.Dl Ic env Ar filename
.Pp
in the kernel config file.
The file can contain lines of the form
.Pp
.Dl name = "value"  # this is a comment
.Pp
where whitespace around name and '=', and
everything after a '#' character, are ignored.  Almost any printable
character except '=' is acceptable as part of a name.  Quotes
are optional and necessary only if the value contains
whitespace.
.Sh SEE ALSO
.Xr kenv 2 ,
.Xr config 5 ,
.Xr loader.conf 5 ,
.Xr loader 8
.Sh HISTORY
The
.Nm
utility appeared in
.Fx 4.1.1 .