mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-11 07:40:05 +00:00
60 lines
1.5 KiB
C
60 lines
1.5 KiB
C
/* Copyright (C) 1991, 1992, 1993, 1995 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 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., 675 Mass Ave,
|
|
Cambridge, MA 02139, USA. */
|
|
|
|
#include <ansidecl.h>
|
|
#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
|
|
DEFUN(__dup2, (fd, fd2), int fd AND int fd2)
|
|
{
|
|
int save;
|
|
|
|
if (fd2 < 0
|
|
#ifdef OPEN_MAX
|
|
|| fd2 >= OPEN_MAX
|
|
#endif
|
|
)
|
|
{
|
|
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);
|
|
errno = save;
|
|
|
|
return fcntl (fd, F_DUPFD, fd2);
|
|
}
|
|
|
|
weak_alias (__dup2, dup2)
|