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Edit File: termios-tcflow.h

/* termios tcflag symbolic contants definitions.  Linux/generic version.
   Copyright (C) 2019-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

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, see
   <https://www.gnu.org/licenses/>.  */

#ifndef _TERMIOS_H
# error "Never include <bits/termios-tcflow.h> directly; use <termios.h> instead."
#endif

/* tcsetattr uses these.  */
#define	TCSANOW		0
#define	TCSADRAIN	1
#define	TCSAFLUSH	2