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glibc  2.9
io.h
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00001 /* Copyright (C) 1996, 1998, 1999 Free Software Foundation, Inc.
00002    This file is part of the GNU C Library.
00003 
00004    The GNU C Library is free software; you can redistribute it and/or
00005    modify it under the terms of the GNU Lesser General Public
00006    License as published by the Free Software Foundation; either
00007    version 2.1 of the License, or (at your option) any later version.
00008 
00009    The GNU C Library is distributed in the hope that it will be useful,
00010    but WITHOUT ANY WARRANTY; without even the implied warranty of
00011    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012    Lesser General Public License for more details.
00013 
00014    You should have received a copy of the GNU Lesser General Public
00015    License along with the GNU C Library; if not, write to the Free
00016    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00017    02111-1307 USA.  */
00018 
00019 #ifndef       _SYS_IO_H
00020 
00021 #define       _SYS_IO_H     1
00022 #include <features.h>
00023 
00024 __BEGIN_DECLS
00025 
00026 /* If TURN_ON is TRUE, request for permission to do direct i/o on the
00027    port numbers in the range [FROM,FROM+NUM-1].  Otherwise, turn I/O
00028    permission off for that range.  This call requires root privileges.  */
00029 extern int ioperm (unsigned long int __from, unsigned long int __num,
00030                  int __turn_on) __THROW;
00031 
00032 /* Set the I/O privilege level to LEVEL.  If LEVEL is nonzero,
00033    permission to access any I/O port is granted.  This call requires
00034    root privileges. */
00035 extern int iopl (int __level) __THROW;
00036 
00037 /* The functions that actually perform reads and writes.  */
00038 extern unsigned char inb (unsigned long int port) __THROW;
00039 extern unsigned short int inw (unsigned long int port) __THROW;
00040 extern unsigned long int inl (unsigned long int port) __THROW;
00041 
00042 extern void outb (unsigned char value, unsigned long int port) __THROW;
00043 extern void outw (unsigned short value, unsigned long int port) __THROW;
00044 extern void outl (unsigned long value, unsigned long int port) __THROW;
00045 
00046 __END_DECLS
00047 
00048 #endif /* _SYS_IO_H */