login/unlockpt.c

   1 /* Copyright (C) 1998-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998.
   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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <stdlib.h>
  20 #include <errno.h>
  21
  22 /* Given a fd on a master pseudoterminal, clear a kernel lock so that
  23    the slave can be opened.  This is to avoid a race between opening the
  24    master and calling grantpt() to take possession of the slave. */
  25 int
  26 unlockpt (int fd __attribute__ ((unused)))
  27 {
  28   __set_errno (ENOSYS);
  29   return -1;
  30 }
  31
  32 stub_warning (unlockpt)