glibc/io/dup3.c

45 lines
1.3 KiB
C

/* Copyright (C) 2008-2016 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 <unistd.h>
/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
open the same file as FD is which setting flags according to
FLAGS. Return FD2 or -1. */
int
__dup3 (int fd, int fd2, int flags)
{
if (fd < 0 || fd2 < 0)
{
__set_errno (EBADF);
return -1;
}
if (fd == fd2)
/* No way to check that they are valid. */
return fd2;
__set_errno (ENOSYS);
return -1;
}
libc_hidden_def (__dup3)
weak_alias (__dup3, dup3)
stub_warning (dup3)