.\" $OpenBSD: modload.8,v 1.27 2013/07/16 09:45:28 schwarze Exp $
.\" $NetBSD: modload.8,v 1.17 2001/11/16 11:57:16 wiz Exp $
.\"
.\" Copyright (c) 1993 Christopher G. Demetriou
.\" All rights reserved.
.\"
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.\"    must display the following acknowledgement:
.\"          This product includes software developed for the
.\"          NetBSD Project.  See http://www.netbsd.org/ for
.\"          information about NetBSD.
.\" 4. The name of the author may not be used to endorse or promote products
.\"    derived from this software without specific prior written permission.
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.\" <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
.\"
.Dd $Mdocdate: July 16 2013 $
.Dt MODLOAD 8
.Os
.Sh NAME
.Nm modload
.Nd load a kernel module
.Sh SYNOPSIS
.Nm modload
.Op Fl dnSsv
.Op Fl A Ar kernel
.Op Fl e Ar entry
.Op Fl o Ar output_file
.Op Fl p Ar postinstall
.Ar input_file
.Sh DESCRIPTION
The
.Nm
utility loads a loadable kernel module into a running system.
The input file is an object file (.o file).
.Pp
The options to
.Nm
are as follows:
.Bl -tag -width Ds
.It Fl A Ar kernel
Specify the file that is passed to the linker
to resolve module references to external symbols.
The symbol file must be for the currently running
kernel or the module is likely to crash the system.
.It Fl d
Debug.
Used to debug
.Nm
itself.
.It Fl e Ar entry
Specify the module entry point.
This is passed by
.Nm
to
.Xr ld 1
when the module is linked.
The default module entry point name is `xxxinit'.
If `xxxinit' cannot be found, an attempt to use `<module_name>_lkmentry'
will be made, where <module_name> is the filename being loaded without
the `.o'.
.It Fl n
Do everything, except calling the module entry point (and any
post-install program).
.It Fl o Ar output_file
Specify the name of the output file that is produced by
the linker.
.It Fl p Ar postinstall
Specify the name of a shell script or program that will
be executed if the module is successfully loaded.
It is always passed the module id (in decimal) and module
type (in hexadecimal) as the first two arguments.
For loadable drivers, the third argument is
the block or character major device number.
For a loadable system call, the third argument is the system
call number.
.It Fl S
Do not remove the temporary object file.
By default, the
.Xr ld 1
output is removed after being loaded into the kernel.
.It Fl s
Do not load symbols from the kernel module.
.It Fl v
Print comments about the loading process.
.El
.Sh FILES
.Bl -tag -width "/usr/include/sys/lkm.hXXX" -compact
.It Pa /dev/ksyms
Default file passed to the linker to resolve external
references in the module.
.It Pa /usr/include/sys/lkm.h
File containing definitions of module types.
.El
.Sh EXIT STATUS
The
.Nm
utility exits with a status of 0 on success
and with a nonzero status if an error occurs.
.Sh SEE ALSO
.Xr ld 1 ,
.Xr lkm 4 ,
.Xr securelevel 7 ,
.Xr modstat 8 ,
.Xr modunload 8
.Sh HISTORY
The
.Nm
command was designed to be similar in functionality
to the corresponding command in
.Tn "SunOS 4.1.3" .
.Sh AUTHORS
.An Terrence R. Lambert Aq Mt terry@cs.weber.edu
.Sh BUGS
.Bl -bullet
.It
The loadable device driver framework can
only reserve either a character or block device entry, not both.
.It
Loading the symbol table is expensive in terms of space:
it presently duplicates all the kernel symbols for each lkm loaded
with
.Fl s .
.El