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.\" $FreeBSD$
.\"
.Dd October 12, 2020
.Dt DEVMATCH 8
.Os
.Sh NAME
.Nm devmatch
.Nd print information about unattached devices
.Sh SYNOPSIS
.Nm
.Op Fl adhpuv
.Op Fl -all
.Op Fl -dump
.Op Fl -hints Ar file
.Op Fl -nomatch Ar event
.Op Fl -unbound
.Op Fl -verbose
.Sh DESCRIPTION
The
.Nm
utility, without any arguments, prints all the kernel modules it has
found for all the unattached, enabled devices in the system.
.Bl -tag -width 20m
.It Fl a Fl -all
Include all devices, not just the ones that are unattached.
.It Fl d Fl -dump
Produce a human readable dump of the
.Pa linker.hints
file.
.It Fl h Fl -hints Ar file
Use the named
.Ar file
instead of
.Pa linker.hints
guessed from the current module load path.
.It Fl p Fl -nomatch Ar event
Parse and use a standard NOMATCH event from
.Xr devd 8
for matching instead of searching the device tree.
.It Fl u Fl -unbound
Attempt to produce a list of those drivers with PNP info whose driver
tables with that PNP info can not be found.
.It Fl v Fl -verbose
Produce more verbose output.
.El
.Sh SEE ALSO
.Xr devinfo 8 ,
.Xr MODULE_PNP_INFO 9
.Sh AUTHORS
.An Warner Losh Aq Mt imp@FreeBSD.org
.Sh BUGS
The kernel has hints in it, but we exclude it from the list of modules
to suggest for unmatched devices.
We exclude it when suggesting drivers, but include it when looking for
unbound devices or producing a full dump of
.Pa linker.hints .
This can be confusing.
.Pp
Some modules are hard links in
.Pa /boot/kernel
and will be reported twice.
.Pp
The PNP string's attributes are evaluated once per PNP entry on that
bus rather than once.
.Pp
The term PNP is overloaded in FreeBSD.
It means, generically, the identifying data the bus provides about a
device.
While this include old ISA PNP identifiers, it also includes the
logical equivalent in USB, PCI, and others.
.Pp
Many drivers currently lack proper PNP table decorations and need to
be updated.
.Sh HISTORY
.Nm
first appeared in
.Fx 12.0 .