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tcsendbreak(3p) — Linux manual page

TCSENDBREAK(3P)         POSIX Programmer's ManualTCSENDBREAK(3P)

PROLOG        top

       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        top

       tcsendbreak — send a break for a specific duration

SYNOPSIS        top

       #include <termios.h>       int tcsendbreak(intfildes, intduration);

DESCRIPTION        top

       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. Ifduration is 0, it       shall cause transmission of zero-valued bits for at least 0.25       seconds, and not more than 0.5 seconds. Ifduration is not 0, it       shall send zero-valued bits for an implementation-defined period       of time.       Thefildes argument is an open file descriptor associated with a       terminal.       If the terminal is not using asynchronous serial data       transmission, it is implementation-defined whethertcsendbreak()       sends data to generate a break condition or returns without taking       any action.       Attempts to usetcsendbreak() from a process which is a member of       a background process group on afildes 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        top

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

ERRORS        top

       Thetcsendbreak() function shall fail if:EBADFThefildes argument is not a valid file descriptor.EIOThe process group of the writing process is orphaned, the              calling thread is not blocking SIGTTOU, and the process is              not ignoring SIGTTOU.ENOTTYThe file associated withfildes is not a terminal.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

       The Base Definitions volume of POSIX.1‐2017,Chapter 11,GeneralTerminal Interface,termios.h(0p)

COPYRIGHT        top

       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 athttp://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, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017TCSENDBREAK(3P)

Pages that refer to this page:termios.h(0p), tcflow(3p)

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