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/* Copyright (C) 1991-2014 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 <fcntl.h>
#include <limits.h>
#include <unistd.h>
/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
open the same file as FD is. Return FD2 or -1. */
int
__dup2 (fd, fd2)
int fd;
int fd2;
{
int save;
if (fd2 < 0
#ifdef OPEN_MAX
|| fd2 >= OPEN_MAX
#endif
)
{
__set_errno (EBADF);
return -1;
}
/* Check if FD is kosher. */
if (fcntl (fd, F_GETFL) < 0)
return -1;
if (fd == fd2)
return fd2;
/* This is not atomic. */
save = errno;
(void) close (fd2);
__set_errno (save);
return fcntl (fd, F_DUPFD, fd2);
}
libc_hidden_def (__dup2)
weak_alias (__dup2, dup2)
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