TCFLUSH(3)                 POSIX Programmer's Manual                TCFLUSH(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
       tcflush -- flush non-transmitted output data, non-read input data, or
       both

SSYYNNOOPPSSIISS
       #include <termios.h>

       int tcflush(int _f_i_l_d_e_s, int _q_u_e_u_e___s_e_l_e_c_t_o_r);

DDEESSCCRRIIPPTTIIOONN
       Upon successful completion, _t_c_f_l_u_s_h() shall discard data written to the
       object referred to by _f_i_l_d_e_s (an open file descriptor associated with a
       terminal) but not transmitted, or data received but not read, depending
       on the value of _q_u_e_u_e___s_e_l_e_c_t_o_r:

        *  If _q_u_e_u_e___s_e_l_e_c_t_o_r is TCIFLUSH, it shall flush data received but not
           read.

        *  If _q_u_e_u_e___s_e_l_e_c_t_o_r is TCOFLUSH, it shall flush data written but not
           transmitted.

        *  If _q_u_e_u_e___s_e_l_e_c_t_o_r is TCIOFLUSH, it shall flush both data received
           but not read and data written but not transmitted.

       Attempts to use _t_c_f_l_u_s_h() 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_f_l_u_s_h() function shall fail if:

       EEBBAADDFF  The _f_i_l_d_e_s argument is not a valid file descriptor.

       EEIINNVVAALL The _q_u_e_u_e___s_e_l_e_c_t_o_r argument is not a supported value.

       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
       _t_c_d_r_a_i_n()

       The Base Definitions volume of POSIX.1-2008, _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, 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 .



IEEE/The Open Group                  2013                           TCFLUSH(3)
