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KENV(1)			FreeBSD	General	Commands Manual		       KENV(1)

NAME
     kenv -- dump or modify the	kernel environment

SYNOPSIS
     kenv [-hNq]
     kenv [-qv]	variable[=value]
     kenv [-q] -u variable

DESCRIPTION
     The kenv utility will dump	the kernel environment if invoked without ar-
     guments.  If the -h option	is specified, it will limit the	report to ker-
     nel probe hints.  If an optional variable name is specified, kenv will
     only report that value.  If the -N	option is specified, kenv will only
     display variable names and	not their values.  If the -u option is speci-
     fied, kenv	will delete the	given environment variable.  If	the environ-
     ment variable is followed by an optional value, kenv will set the envi-
     ronment variable to this value.

     If	the -q option is set, warnings normally	printed	as a result of being
     unable to perform the requested operation will be suppressed.

     If	the -v option is set, the variable name	will be	printed	out for	the
     environment variable in addition to the value when	kenv is	executed with
     a variable	name.

     Variables can be added to the kernel environment using the
     /boot/loader.conf file, or	also statically	compiled into the kernel using
     the statement

	   env filename

     in	the kernel config file.	 The file can contain lines of the form

	   name	= value	# this is a comment

     where whitespace around `name' and	`=', and everything after a `#'	char-
     acter, are	ignored.  Almost any printable character except	`=' is accept-
     able as part of a name.  Quotes are optional and necessary	only if	the
     value contains whitespace.

EXAMPLES
     Show kernel probe hints variable names and	filter for the uart device

	   $ kenv -h -N	| grep uart
	   hint.uart.0.at
	   hint.uart.0.flags
	   hint.uart.0.irq
	   hint.uart.0.port
	   hint.uart.1.at
	   hint.uart.1.irq
	   hint.uart.1.port

     Show the value of a specific variable:

	   $ kenv hint.uart.1.at
	   isa

     Same as above but adding the name of the variable in the report:

	   $ kenv -v hint.uart.1.at
	   hint.uart.1.at="isa"

     Try to delete a variable and suppress warnings if any:

	   $ kenv -q -u	hint.uart.1.at

     Set the value of the verbose_loading variable

	   $ kenv verbose_loading="YES"
	   verbose_loading="YES"

SEE ALSO
     kenv(2), config(5), loader.conf(5), loader(8)

HISTORY
     The kenv utility appeared in FreeBSD 4.1.1.

FreeBSD	13.0			October	5, 2020			  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | SEE ALSO | HISTORY

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