TCFLUSH(3P) POSIX Programmer's Manual TCFLUSH(3P)PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding
Linux manual page for details of Linux behavior), or the interface may
not be implemented on Linux.
NAMEtcflush — flush non-transmitted output data, non-read input data, or
both
SYNOPSIS
#include <termios.h>
int tcflush(int fildes, int queue_selector);
DESCRIPTION
Upon successful completion, tcflush() shall discard data written to the
object referred to by fildes (an open file descriptor associated with a
terminal) but not transmitted, or data received but not read, depending
on the value of queue_selector:
* If queue_selector is TCIFLUSH, it shall flush data received but not
read.
* If queue_selector is TCOFLUSH, it shall flush data written but not
transmitted.
* If queue_selector is TCIOFLUSH, it shall flush both data received
but not read and data written but not transmitted.
Attempts to use tcflush() from a process which is a member of a back‐
ground process group on a fildes associated with its controlling termi‐
nal shall cause the process group to be sent a SIGTTOU signal. If the
calling thread is blocking SIGTTOU signals or the process is ignoring
SIGTTOU signals, the process shall be allowed to perform the operation,
and no signal is sent.
RETURN VALUE
Upon successful completion, 0 shall be returned. Otherwise, −1 shall be
returned and errno set to indicate the error.
ERRORS
The tcflush() function shall fail if:
EBADF The fildes argument is not a valid file descriptor.
EINVAL The queue_selector argument is not a supported value.
EIO The process group of the writing process is orphaned, the call‐
ing thread is not blocking SIGTTOU, and the process is not
ignoring SIGTTOU.
ENOTTY The file associated with fildes is not a terminal.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSOtcdrain()
The Base Definitions volume of POSIX.1‐2008, Chapter 11, General Termi‐
nal Interface, <termios.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
cal and Electronics Engineers, Inc and The Open Group. (This is
POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the source
files to man page format. To report such errors, see https://www.ker‐
nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 TCFLUSH(3P)
