tcsendbreak(3)

tcsendbreak3

Send a continuous stream of zero-valued bits

Usage

#include <termios.h>

int tcsendbreak(int fd, int duration);

Library

Standard C library (libc, -lc)

Overview

tcsendbreak() transmits a continuous stream of zero-valued bits for a specific duration, if the terminal is using asynchronous serial data transmission.

If duration is zero, it transmits zero-valued bits for at least 0.25 seconds, and not more than 0.5 seconds.

If duration is not zero, it sends zero-valued bits for some implementation-defined length of time.

If the terminal is not using asynchronous serial data transmission, tcsendbreak() returns without taking any action.

Return value

0

on success.

-1

on failure and set errno to indicate the error.

Attributes

For an explanation of the terms used in this section, see attributes(7).

InterfaceAttributeValue
tcsendbreak()Thread safetyMT-Safe

Versions

The effect of a nonzero duration with tcsendbreak() varies. SunOS specifies a break of duration * N seconds, where N is at least 0.25, and not more than 0.5. Linux, AIX, DU, Tru64 send a break of duration milliseconds. FreeBSD and NetBSD and HP-UX and MacOS ignore the value of duration. Under Solaris and UnixWare, tcsendbreak() with nonzero duration behaves like tcdrain(3).

Releases

19 releases since Debian 1.1 (Buzz); the text changed 15 times.

  1. 1.1–1.3
  2. 2.0–2.1
  3. 2.2
  4. 3.0
  5. 3.1
  6. 4.0
  7. 5.0
  8. 6.0
  9. 7
  10. 8
  11. 9
  12. 10
  13. 11
  14. 12
  15. 13
  16. Arch

Standards

POSIX.1-2008.

History

POSIX.1-2001.

From man-pages 6.19-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.