TCSENDBREAK(3)             POSIX Programmer's Manual            TCSENDBREAK(3)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       tcsendbreak -- send a break for a specific duration

SSYYNNOOPPSSIISS
       #include <termios.h>

       int tcsendbreak(int _f_i_l_d_e_s, int _d_u_r_a_t_i_o_n);

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

       The _f_i_l_d_e_s 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 _t_c_s_e_n_d_b_r_e_a_k() sends data to generate
       a break condition or returns without taking any action.

       Attempts to use _t_c_s_e_n_d_b_r_e_a_k() from a process which is a member of a
       background process group on a _f_i_l_d_e_s 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.

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

EERRRROORRSS
       The _t_c_s_e_n_d_b_r_e_a_k() function shall fail if:

       EEBBAADDFF  The _f_i_l_d_e_s argument is not a valid file descriptor.

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

       EENNOOTTTTYY The file associated with _f_i_l_d_e_s is not a terminal.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
       None.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       None.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       The Base Definitions volume of POSIX.1-2017, _C_h_a_p_t_e_r _1_1, _G_e_n_e_r_a_l
       _T_e_r_m_i_n_a_l _I_n_t_e_r_f_a_c_e, <<tteerrmmiiooss..hh>>

CCOOPPYYRRIIGGHHTT
       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(3)
