include/sys/uio.h

   1 /* Copyright (C) 1991, 92, 96, 97, 98, 99, 2003 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, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #ifndef _SYS_UIO_H
  19 #define _SYS_UIO_H      1
  20
  21 #include <features.h>
  22
  23 #include <sys/types.h>
  24
  25 __BEGIN_DECLS
  26
  27 /* This file defines `struct iovec'.  */
  28 #include <bits/uio.h>
  29
  30
  31 /* Read data from file descriptor FD, and put the result in the
  32    buffers described by IOVEC, which is a vector of COUNT `struct iovec's.
  33    The buffers are filled in the order specified.
  34    Operates just like `read' (see <unistd.h>) except that data are
  35    put in IOVEC instead of a contiguous buffer.
  36
  37    This function is a cancellation point and therefore not marked with
  38    __THROW.  */
  39 extern ssize_t readv (int __fd, const struct iovec *__iovec, int __count);
  40
  41 /* Write data pointed by the buffers described by IOVEC, which
  42    is a vector of COUNT `struct iovec's, to file descriptor FD.
  43    The data is written in the order specified.
  44    Operates just like `write' (see <unistd.h>) except that the data
  45    are taken from IOVEC instead of a contiguous buffer.
  46
  47    This function is a cancellation point and therefore not marked with
  48    __THROW.  */
  49 extern ssize_t writev (int __fd, const struct iovec *__iovec, int __count);
  50
  51 #ifdef __USE_MISC
  52 /* Read data from file descriptor FD at the given position OFFSET
  53    without change the file pointer, and put the result in the buffers
  54    described by IOVEC, which is a vector of COUNT 'struct iovec's.
  55    The buffers are filled in the order specified.  Operates just like
  56    'pread' (see <unistd.h>) except that data are put in IOVEC instead
  57    of a contiguous buffer.
  58
  59    This function is a cancellation point and therefore not marked with
  60    __THROW.  */
  61 extern ssize_t preadv (int __fd, const struct iovec *__iovec, int __count,
  62                        __off_t __offset) __wur;
  63
  64 /* Write data pointed by the buffers described by IOVEC, which is a
  65    vector of COUNT 'struct iovec's, to file descriptor FD at the given
  66    position OFFSET without change the file pointer.  The data is
  67    written in the order specified.  Operates just like 'pwrite' (see
  68    <unistd.h>) except that the data are taken from IOVEC instead of a
  69    contiguous buffer.
  70
  71    This function is a cancellation point and therefore not marked with
  72    __THROW.  */
  73 extern ssize_t pwritev (int __fd, const struct iovec *__iovec, int __count,
  74                         __off_t __offset) __wur;
  75 #endif  /* Use misc.  */
  76
  77 __END_DECLS
  78
  79 #endif /* sys/uio.h */