misc/sys/uio.h

   1 /* Copyright (C) 1991, 1992 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the, 1992 Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #ifndef _SYS_UIO_H
  20
  21 #define _SYS_UIO_H      1
  22 #include <features.h>
  23
  24 __BEGIN_DECLS
  25
  26 #define __need_size_t
  27 #include <stddef.h>
  28
  29
  30 /* Structure describing a section of memory.  */
  31
  32 struct iovec
  33 {
  34   /* Starting address.  */
  35   __ptr_t iov_base;
  36   /* Length in bytes.  */
  37   size_t iov_len;
  38 };
  39
  40
  41 /* Read data from file descriptor FD, and put the result in the
  42    buffers described by VECTOR, which is a vector of COUNT `struct iovec's.
  43    The buffers are filled in the order specified.
  44    Operates just like `read' (see <unistd.h>) except that data are
  45    put in VECTOR instead of a contiguous buffer.  */
  46 int readv __P ((int __fd, __const struct iovec * __vector, size_t __count));
  47
  48 /* Write data pointed by the buffers described by VECTOR, which
  49    is a vector of COUNT `struct iovec's, to file descriptor FD.
  50    The data is written in the order specified.
  51    Operates just like `write' (see <unistd.h>) except that the data
  52    are taken from VECTOR instead of a contiguous buffer.  */
  53 int writev __P ((int __fd, __const struct iovec * __vector, size_t __count));
  54
  55
  56 __END_DECLS
  57
  58 #endif /* sys/uio.h */