glibc/sysdeps/unix/sysv/linux/llseek.c

47 lines
1.6 KiB
C

/* Long-long seek operation.
Copyright (C) 1996-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <sys/types.h>
#include <sysdep.h>
#include <sys/syscall.h>
/* Seek to OFFSET on FD, starting from WHENCE. */
extern loff_t __llseek (int fd, loff_t offset, int whence);
loff_t
__llseek (int fd, loff_t offset, int whence)
{
loff_t retval;
return (loff_t) (INLINE_SYSCALL (_llseek, 5, fd, (off_t) (offset >> 32),
(off_t) (offset & 0xffffffff),
__ptrvalue (&retval), whence) ?: retval);
}
weak_alias (__llseek, llseek)
strong_alias (__llseek, __libc_lseek64)
strong_alias (__llseek, __lseek64)
weak_alias (__llseek, lseek64)
/* llseek doesn't have a prototype. Since the second parameter is a
64bit type, this results in wrong behaviour if no prototype is
provided. */
link_warning (llseek, "\
the `llseek' function may be dangerous; use `lseek64' instead.")