.\" Copyright (c) 2013-2026 Devin Teske <dteske@FreeBSD.org>
.\" Copyright (c) 2021-2026 Faraz Vahedi <kfv@FreeBSD.org>
.\"
.\" SPDX-License-Identifier: BSD-2-Clause
.\"
.Dd August 2, 2026
.Dt SYSCONF-LOADER 8
.Os
.Sh NAME
.Nm "sysconf loader"
.Nd configure boot loader directives
.Sh SYNOPSIS
.Nm sysconf
.Cm loader
.Op Fl AcDeFinNqvVx
.Op Fl j Ar jail | Fl R Ar dir
.Op Fl f Ar file
.Ar name Ns Op Ns Oo +|- Oc Ns = Ns Ar value
.Ar ...
.Nm sysconf
.Cm loader
.Op Fl ADeFnNqvV
.Op Fl f Ar file
.Fl a
.Nm sysconf
.Cm loader
.Op Fl AaDinNq
.Fl d
.Op Ar name ...
.Nm sysconf
.Cm loader
.Op Fl E
.Fl l | L
.Sh DESCRIPTION
The
.Cm loader
target of
.Xr sysconf 8
reads and modifies
.Xr loader.conf 5
configuration.
Shared assignment syntax and options are documented in
.Xr sysconf 8 ;
multi-file write policy in
.Xr sysconf-targets 8 .
.Pp
The file list is not hardcoded:
just as the boot loader itself hardcodes only
.Pa /boot/defaults/loader.conf ,
.Nm sysconf
names that defaults file and the
.Va loader_conf_files ,
.Va loader_conf_dirs ,
and
.Va local_loader_conf_files
directives so that discovery matches the loader
.Pq see Xr bsdconf_format 3 and Xr loader.conf 5 .
On a stock system this resolves to
.Pa /boot/device.hints ,
.Pa /boot/loader.conf ,
.Pa /boot/loader.conf.d/*.conf ,
and
.Pa /boot/loader.conf.local ,
in that order;
when the defaults file is missing,
that stock list is assumed.
.Pp
Values written for this target are always enclosed in quotes
.Pq quoted or unquoted input is accepted
with no whitespace around the equals sign,
as demanded by the boot loader's reader.
.Pp
The defaults file
.Pa /boot/defaults/loader.conf
.Pq or Ev LOADER_DEFAULTS
additionally supports
.Fl d ,
.Fl D ,
and
.Fl A
.Pq see Xr sysconf-targets 8 .
Space-separated list directives such as
.Va kernels
use
.Ar name Ns += Ns Ar word
and
.Ar name Ns -= Ns Ar word
as described in
.Xr sysconf 8 .
.Sh ENVIRONMENT
.Bl -tag -width "LOADER_DEFAULTS"
.It Ev LOADER_DEFAULTS
Defaults file consulted in place of
.Pa /boot/defaults/loader.conf
for file-list discovery and for
.Fl d ,
.Fl D ,
and
.Fl A
.Po
in the vein of
.Ev RC_DEFAULTS
in
.Xr sysrc 8
.Pc .
The value is used verbatim
.Pq not subject to Fl R .
.El
.Sh FILES
.Bl -tag -width "/boot/defaults/loader.conf" -compact
.It Pa /boot/defaults/loader.conf
Defaults and the authority on the file list.
.It Pa /boot/device.hints
First in the stock
.Va loader_conf_files
list.
.It Pa /boot/loader.conf
Stock write target.
.It Pa /boot/loader.conf.d/
Drop-in directory.
.It Pa /boot/loader.conf.local
Site-local overrides,
sourced last.
.El
.Sh EXAMPLES
.Dl sysconf loader zfs_load
.Dl sysconf loader zfs_load=\(dqYES\(dq
.Dl sysconf loader -l
.Dl sysconf loader -d verbose_loading
.Dl sysconf loader -Ad
.Dl sysconf loader -D verbose_loading
.Dl sysconf loader -aD
.Dl sysconf loader -A
.Dl sysconf loader kernels+=kernel_test
.Dl sysconf loader kernels-=kernel_test
.Dl sysconf -a loader
.Dl sysconf loader -f /tmp/loader.conf.new zfs_load=\(dqYES\(dq
.Sh SEE ALSO
.Xr bsdconf_format 3 ,
.Xr loader.conf 5 ,
.Xr sysconf 8 ,
.Xr sysconf-targets 8
.Sh HISTORY
The
.Nm sysconf
utility first appeared in
.Fx 16.0 .
.Sh AUTHORS
.An Devin Teske Aq Mt dteske@FreeBSD.org
.An Faraz Vahedi Aq Mt kfv@FreeBSD.org