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+++ b/lib/pty-private.h
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+/* Interface to the pt_chown program.
+   Copyright (C) 1998, 1999, 2009, 2010 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _PTY_PRIVATE_H
+#define _PTY_PRIVATE_H 1
+
+/* The group slave pseudo terminals belong to.  */
+#define TTY_GROUP "tty"
+
+/* The file descriptor connected to the master pseudo terminal.  */
+#define PTY_FILENO 3
+
+/* Path to the helper program that implements `grantpt' in user space.  */
+#define _PATH_PT_CHOWN PKGLIBEXECDIR "/pt_chown"
+
+/* Test whether given TTY is really a Unix98 pseudo terminal.  */
+/* #define unix98_pseudo_p(Dev) ... */
+
+/* Exit codes for the helper program.  */
+enum  /* failure modes */
+{
+  FAIL_EBADF = 1,
+  FAIL_EINVAL,
+  FAIL_EACCES,
+  FAIL_EXEC,
+  FAIL_ENOMEM
+};
+
+#endif /* pty-private.h  */