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.

NAME

       tcsendbreak — send a break for a specific duration

SYNOPSIS

       #include <termios.h>

       int tcsendbreak(int fildes, int duration);

DESCRIPTION

       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.

RETURN VALUE

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

ERRORS

       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.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       The  Base  Definitions  volume  of  POSIX.1‐2017,  Chapter 11, General Terminal Interface,
       <termios.h>

COPYRIGHT

       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 .