suse man page for tcflow

TCFLOW(3P)						     POSIX Programmer's Manual							TCFLOW(3P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
       tcflow - suspend or restart the transmission or reception of data

SYNOPSIS
       #include <termios.h>

       int tcflow(int fildes, int action);

DESCRIPTION
       The tcflow() function shall suspend or restart transmission or reception of data on the object referred to  by  fildes,	depending  on  the
       value of action. The fildes argument is an open file descriptor associated with a terminal.

	* If action is TCOOFF, output shall be suspended.

	* If action is TCOON, suspended output shall be restarted.

	* If  action  is  TCIOFF,  the system shall transmit a STOP character, which is intended to cause the terminal device to stop transmitting
	  data to the system.

	* If action is TCION, the system shall transmit a START character, which is intended to cause the terminal device  to  start  transmitting
	  data to the system.

       The default on the opening of a terminal file is that neither its input nor its output are suspended.

       Attempts  to use tcflow() from a process which is a member of a background 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 process is blocking or 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 tcflow() function shall fail if:

       EBADF  The fildes argument is not a valid file descriptor.

       EINVAL The action argument is not a supported value.

       ENOTTY The file associated with fildes is not a terminal.

       The tcflow() function may fail if:

       EIO    The process group of the writing process is orphaned, and the writing process is not ignoring or blocking SIGTTOU.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       tcsendbreak(), the Base Definitions volume of IEEE Std 1003.1-2001, Chapter 11, General Terminal Interface, <termios.h>, <unistd.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- 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 .

IEEE
/The Open Group						       2003								TCFLOW(3P)