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tcsendbreak(3posix)


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.12008,  Chapter  11,  General
   Terminal 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
   Electrical 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.kernel.org/doc/man-pages/reporting_bugs.html .



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