login/forkpty.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 <sys/types.h>
  20 #include <termios.h>
  21 #include <unistd.h>
  22 #include <utmp.h>
  23 #include <pty.h>
  24
  25 int
  26 forkpty (amaster, name, termp, winp)
  27      int *amaster;
  28      char *name;
  29      const struct termios *termp;
  30      const struct winsize *winp;
  31 {
  32   int master, slave, pid;
  33
  34   if (openpty (&master, &slave, name, termp, winp) == -1)
  35     return -1;
  36
  37   switch (pid = fork ())
  38     {
  39     case -1:
  40       close (master);
  41       close (slave);
  42       return -1;
  43     case 0:
  44       /* Child.  */
  45       close (master);
  46       if (login_tty (slave))
  47         _exit (1);
  48
  49       return 0;
  50     default:
  51       /* Parent.  */
  52       *amaster = master;
  53       close (slave);
  54
  55       return pid;
  56     }
  57 }