sysdeps/unix/bsd/tcflush.c

   1 /* Copyright (C) 1991, 1992 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <errno.h>
  21 #include <stddef.h>
  22 #include <termios.h>
  23 #include <unistd.h>
  24 #include "bsdtty.h"
  25 #include <sys/file.h>
  26
  27 /* Flush pending data on FD.  */
  28 int
  29 DEFUN(tcflush, (fd, queue_selector), int fd AND int queue_selector)
  30 {
  31   int arg;
  32
  33   switch (queue_selector)
  34     {
  35     case TCIFLUSH:
  36       arg = FREAD;
  37       break;
  38     case TCOFLUSH:
  39       arg = FWRITE;
  40       break;
  41     case TCIOFLUSH:
  42       arg = FREAD | FWRITE;
  43       break;
  44     default:
  45       errno = EINVAL;
  46       return -1;
  47     }
  48
  49   return __ioctl (fd, TIOCFLUSH, (PTR) &arg);
  50 }