io.h

/* Copyright (C) 1996, 1998, 1999, 2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#ifndef	_SYS_IO_H

#define	_SYS_IO_H	1
#include <features.h>

__BEGIN_DECLS

/* If TURN_ON is TRUE, request for permission to do direct i/o on the
   port numbers in the range [FROM,FROM+NUM-1].  Otherwise, turn I/O
   permission off for that range.  This call requires root privileges.  */
extern int ioperm (unsigned long int __from, unsigned long int __num,
		   int __turn_on) __THROW;

/* Set the I/O privilege level to LEVEL.  If LEVEL is nonzero,
   permission to access any I/O port is granted.  This call requires
   root privileges. */
extern int iopl (int __level) __THROW;

/* The functions that actually perform reads and writes.  */
extern unsigned char inb (unsigned long int port) __THROW;
extern unsigned short int inw (unsigned long int port) __THROW;
extern unsigned long int inl (unsigned long int port) __THROW;

extern void outb (unsigned char value, unsigned long int port) __THROW;
extern void outw (unsigned short value, unsigned long int port) __THROW;
extern void outl (unsigned long value, unsigned long int port) __THROW;

__END_DECLS

#endif /* _SYS_IO_H */