$NetBSD$
Copyright (c) 1996 Joerg Wunsch
All rights reserved.
This program is free software.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
$FreeBSD: src/share/man/man4/man4.i386/io.4,v 1.6.2.2 2000/12/12 10:00:55 ru Exp $
.Dd January 1, 1996 .Dt IO 4 i386 .Os .Sh NAME .Nm io .Nd I/O privilege file .Sh DESCRIPTION f -symbolic This device is obsolete and is provided for compatibility purposes only; use .Xr i386_iopl 2 instead. .Ef
Copyright (c) 1996 Joerg Wunsch
All rights reserved.
This program is free software.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
$FreeBSD: src/share/man/man4/man4.i386/io.4,v 1.6.2.2 2000/12/12 10:00:55 ru Exp $
.Dd January 1, 1996 .Dt IO 4 i386 .Os .Sh NAME .Nm io .Nd I/O privilege file .Sh DESCRIPTION f -symbolic This device is obsolete and is provided for compatibility purposes only; use .Xr i386_iopl 2 instead. .Ef
p After opening
a /dev/io for writing the process is granted full I/O privileges; closing the returned file descriptor does .Em not result in revocation of these privileges. The new I/O privileges can be useful in order to write userland programs that handle some hardware directly.
p The entire access control is handled by the file access permissions of
a /dev/io , so care should be taken in granting rights for this device.
p I/O privilege on access to
a /dev/io is only granted if the kernel was built with the .Dv COMPAT_10 option. .Sh FILES l -tag -width Pa -compact t Pa /dev/io .El .Sh SEE ALSO .Xr mem 4 .Sh HISTORY The .Nm file appeared in .Nx 1.0 after it was in the kernel for some time.