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/* Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <unistd.h>
#include <sysdep.h>
#include <sys/syscall.h>
#include <kernel-features.h>
#if defined __NR_pread || __ASSUME_PREAD_SYSCALL > 0
# if __ASSUME_PREAD_SYSCALL == 0
static ssize_t __emulate_pread (int fd, void *buf, size_t count,
off_t offset) internal_function;
# endif
ssize_t
__pread (fd, buf, count, offset)
int fd;
void *buf;
size_t count;
off_t offset;
{
ssize_t result;
/* First try the syscall. */
result = INLINE_SYSCALL (pread, 5, fd, buf, count, offset, 0);
# if __ASSUME_PREAD_SYSCALL == 0
if (result == -1 && errno == ENOSYS)
/* No system call available. Use the emulation. */
result = __emulate_pread (fd, buf, count, offset);
# endif
return result;
}
weak_alias (__pread, pread)
# define __pread(fd, buf, count, offset) \
static internal_function __emulate_pread (fd, buf, count, offset)
#endif
#if __ASSUME_PREAD_SYSCALL == 0
# include <sysdeps/posix/pread.c>
#endif
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