mirror of https://github.com/mkerrisk/man-pages
99 lines
3.0 KiB
Plaintext
99 lines
3.0 KiB
Plaintext
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
|
|
.TH "TCFLOW" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
|
|
.\" tcflow
|
|
.SH NAME
|
|
tcflow \- suspend or restart the transmission or reception of data
|
|
.SH SYNOPSIS
|
|
.LP
|
|
\fB#include <termios.h>
|
|
.br
|
|
.sp
|
|
int tcflow(int\fP \fIfildes\fP\fB, int\fP \fIaction\fP\fB);
|
|
.br
|
|
\fP
|
|
.SH DESCRIPTION
|
|
.LP
|
|
The \fItcflow\fP() function shall suspend or restart transmission
|
|
or reception of data on the object referred to by
|
|
\fIfildes\fP, depending on the value of \fIaction\fP. The \fIfildes\fP
|
|
argument is an open file descriptor associated with a
|
|
terminal.
|
|
.IP " *" 3
|
|
If \fIaction\fP is TCOOFF, output shall be suspended.
|
|
.LP
|
|
.IP " *" 3
|
|
If \fIaction\fP is TCOON, suspended output shall be restarted.
|
|
.LP
|
|
.IP " *" 3
|
|
If \fIaction\fP is TCIOFF, the system shall transmit a STOP character,
|
|
which is intended to cause the terminal device to stop
|
|
transmitting data to the system.
|
|
.LP
|
|
.IP " *" 3
|
|
If \fIaction\fP is TCION, the system shall transmit a START character,
|
|
which is intended to cause the terminal device to start
|
|
transmitting data to the system.
|
|
.LP
|
|
.LP
|
|
The default on the opening of a terminal file is that neither its
|
|
input nor its output are suspended.
|
|
.LP
|
|
Attempts to use \fItcflow\fP() from a process which is a member of
|
|
a background process group on a \fIfildes\fP associated
|
|
with its controlling terminal, shall cause the process group to be
|
|
sent a SIGTTOU signal. If the calling process is blocking or
|
|
ignoring SIGTTOU signals, the process shall be allowed to perform
|
|
the operation, and no signal is sent.
|
|
.SH RETURN VALUE
|
|
.LP
|
|
Upon successful completion, 0 shall be returned. Otherwise, -1 shall
|
|
be returned and \fIerrno\fP set to indicate the error.
|
|
.SH ERRORS
|
|
.LP
|
|
The \fItcflow\fP() function shall fail if:
|
|
.TP 7
|
|
.B EBADF
|
|
The \fIfildes\fP argument is not a valid file descriptor.
|
|
.TP 7
|
|
.B EINVAL
|
|
The \fIaction\fP argument is not a supported value.
|
|
.TP 7
|
|
.B ENOTTY
|
|
The file associated with \fIfildes\fP is not a terminal.
|
|
.sp
|
|
.LP
|
|
The \fItcflow\fP() function may fail if:
|
|
.TP 7
|
|
.B EIO
|
|
The process group of the writing process is orphaned, and the writing
|
|
process is not ignoring or blocking SIGTTOU.
|
|
.sp
|
|
.LP
|
|
\fIThe following sections are informative.\fP
|
|
.SH EXAMPLES
|
|
.LP
|
|
None.
|
|
.SH APPLICATION USAGE
|
|
.LP
|
|
None.
|
|
.SH RATIONALE
|
|
.LP
|
|
None.
|
|
.SH FUTURE DIRECTIONS
|
|
.LP
|
|
None.
|
|
.SH SEE ALSO
|
|
.LP
|
|
\fItcsendbreak\fP() , the Base Definitions volume of IEEE\ Std\ 1003.1-2001,
|
|
Chapter 11, General Terminal Interface, \fI<termios.h>\fP, \fI<unistd.h>\fP
|
|
.SH COPYRIGHT
|
|
Portions of this text are reprinted and reproduced in electronic form
|
|
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
|
|
-- Portable Operating System Interface (POSIX), The Open Group Base
|
|
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
|
|
Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .
|