sysdeps/mach/hurd/dup2.c

   1 /* Copyright (C) 1991-2022 Free Software Foundation, Inc.
   2
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <unistd.h>
  20
  21 /* Duplicate FD to FD2, closing the old FD2 and making FD2 be
  22    open on the same file as FD is.  Return FD2 or -1.  */
  23 int
  24 __dup2 (int fd, int fd2)
  25 {
  26   int flags = 0;
  27
  28   if (fd2 == fd)
  29     /* See the comment in dup3.  */
  30     flags = -1;
  31
  32   return __dup3 (fd, fd2, flags);
  33 }
  34 libc_hidden_def (__dup2)
  35 weak_alias (__dup2, dup2)