This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface

       None.

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group  Base
       Specifications  Issue  7, 2018 Edition, Copyright (C) 2018 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 .

       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.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                                   TCSENDBREAK(3POSIX)

       If the terminal is using asynchronous serial data transmission, tcsendbreak() shall cause transmission of
       a  continuous  stream  of  zero-valued  bits  for  a  specific duration. If duration is 0, it shall cause
       transmission of zero-valued bits for at least 0.25 seconds, and not more than 0.5 seconds. If duration is
       not 0, it shall send zero-valued bits for an implementation-defined period of time.

       The fildes argument is an open file descriptor associated with a terminal.

       If the terminal is not using asynchronous serial data transmission, it is implementation-defined  whether
       tcsendbreak() sends data to generate a break condition or returns without taking any action.

       Attempts  to use tcsendbreak() from a process which is a member of a background process group on a fildes
       associated with its controlling terminal 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.

       The tcsendbreak() function shall fail if:

       EBADF  The fildes argument is not a valid file descriptor.

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

       ENOTTY The file associated with fildes is not a terminal.

       Thefollowingsectionsareinformative.

       None.

       None.

       tcsendbreak — send a break for a specific duration

       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.

       None.

       Upon successful completion, 0 shall be returned. Otherwise,  -1  shall  be  returned  and  errno  set  to
       indicate the error.

       The Base Definitions volume of POSIX.1‐2017, Chapter11, GeneralTerminalInterface, <termios.h>

       #include <termios.h>

       int tcsendbreak(int fildes, int duration);