sysdeps/unix/bsd/bsd4.4/kfreebsd/bits/uio.h

   1 /* Copyright (C) 1996-1997, 2002 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #if !defined _SYS_UIO_H && !defined _FCNTL_H
  20 # error "Never include <bits/uio.h> directly; use <sys/uio.h> instead."
  21 #endif
  22
  23 #ifndef _BITS_UIO_H
  24 #define _BITS_UIO_H     1
  25
  26 #include <sys/types.h>
  27
  28
  29 /* `struct iovec' -- Structure describing a section of memory.  */
  30
  31 struct iovec
  32 {
  33   /* Starting address.  */
  34   __ptr_t iov_base;
  35   /* Length in bytes.  */
  36   size_t iov_len;
  37 };
  38
  39 /* Maximum number of 'struct iovec's that can be passed to a readv() or
  40    writev() system call.  For larger arrays of 'struct iovec', the libc
  41    uses a single read() or write() call to guarantee atomicity.  */
  42 #define UIO_MAXIOV      1024
  43
  44 #ifdef __USE_MISC
  45 enum    uio_rw { UIO_READ, UIO_WRITE };
  46
  47 /* Segment flag values. */
  48 enum uio_seg {
  49         UIO_USERSPACE,          /* from user data space */
  50         UIO_SYSSPACE,           /* from system space */
  51         UIO_NOCOPY              /* don't copy, already in object */
  52 };
  53 #endif
  54
  55 #endif