1 /* Copyright (C) 1991-2021 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <errno.h>
19 #include <stddef.h>
20 #include <termios.h>
21 #include <unistd.h>
22 #include "bsdtty.h"
23 #include <sys/file.h>
24 
25 /* Flush pending data on FD.  */
26 int
tcflush(int fd,int queue_selector)27 tcflush (int fd, int queue_selector)
28 {
29   int arg;
30 
31   switch (queue_selector)
32     {
33     case TCIFLUSH:
34       arg = FREAD;
35       break;
36     case TCOFLUSH:
37       arg = FWRITE;
38       break;
39     case TCIOFLUSH:
40       arg = FREAD | FWRITE;
41       break;
42     default:
43       __set_errno (EINVAL);
44       return -1;
45     }
46 
47   return __ioctl (fd, TIOCFLUSH, (void *) &arg);
48 }
49