lib/dirfd.c

   1 /* dirfd.c -- return the file descriptor associated with an open DIR*
   2
   3    Copyright (C) 2001, 2006, 2008-2024 Free Software Foundation, Inc.
   4
   5    This file is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    This file 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
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Jim Meyering. */
  19
  20 #include <config.h>
  21
  22 #include <dirent.h>
  23 #include <errno.h>
  24
  25 #if GNULIB_defined_DIR
  26 # include "dirent-private.h"
  27 #endif
  28
  29 int
  30 dirfd (DIR *dir_p)
  31 {
  32 #if GNULIB_defined_DIR
  33   int fd = dir_p->fd_to_close;
  34   if (fd == -1)
  35     errno = EINVAL;
  36   return fd;
  37 #else
  38   int fd = DIR_TO_FD (dir_p);
  39   if (fd == -1)
  40     errno = ENOTSUP;
  41
  42   return fd;
  43 #endif
  44 }