+++ /dev/null
-.\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu)
-.\" Portions extracted from linux/kernel/ioport.c (no copyright notice).
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" Modified Tue Aug 1 16:47 1995 by Jochen Karrer
-.\" <cip307@cip.physik.uni-wuerzburg.de>
-.\" Modified Tue Oct 22 08:11:14 EDT 1996 by Eric S. Raymond <esr@thyrsus.com>
-.\" Modified Fri Nov 27 14:50:36 CET 1998 by Andries Brouwer <aeb@cwi.nl>
-.\" Modified, 27 May 2004, Michael Kerrisk <mtk.manpages@gmail.com>
-.\" Added notes on capability requirements
-.\"
-.TH IOPL 2 2013-03-15 "Linux" "Linux Programmer's Manual"
-.SH NAME
-iopl \- change I/O privilege level
-.SH SYNOPSIS
-.B #include <sys/io.h>
-.sp
-.BI "int iopl(int " level );
-.SH DESCRIPTION
-.BR iopl ()
-changes the I/O privilege level of the calling process,
-as specified by the two least significant bits in
-.IR level .
-
-This call is necessary to allow 8514-compatible X servers to run under
-Linux.
-Since these X servers require access to all 65536 I/O ports, the
-.BR ioperm (2)
-call is not sufficient.
-
-In addition to granting unrestricted I/O port access, running at a higher
-I/O privilege level also allows the process to disable interrupts.
-This will probably crash the system, and is not recommended.
-
-Permissions are inherited by
-.BR fork (2)
-and
-.BR execve (2).
-
-The I/O privilege level for a normal process is 0.
-
-This call is mostly for the i386 architecture.
-On many other architectures it does not exist or will always
-return an error.
-.SH RETURN VALUE
-On success, zero is returned.
-On error, \-1 is returned, and
-.I errno
-is set appropriately.
-.SH ERRORS
-.TP
-.B EINVAL
-.I level
-is greater than 3.
-.TP
-.B ENOSYS
-This call is unimplemented.
-.TP
-.B EPERM
-The calling process has insufficient privilege to call
-.BR iopl ();
-the
-.B CAP_SYS_RAWIO
-capability is required to raise the I/O privilege level
-above its current value.
-.SH CONFORMING TO
-.BR iopl ()
-is Linux-specific and should not be used in programs that are
-intended to be portable.
-.SH NOTES
-Libc5 treats it as a system call and has a prototype in
-.IR <unistd.h> .
-Glibc1 does not have a prototype.
-Glibc2 has a prototype both in
-.I <sys/io.h>
-and in
-.IR <sys/perm.h> .
-Avoid the latter, it is available on i386 only.
-.SH SEE ALSO
-.BR ioperm (2),
-.BR outb (2),
-.BR capabilities (7)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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