| tcsendbreak(3) | Library Functions Manual | tcsendbreak(3) |
NAME
tcsendbreak - send a continuous stream of zero-valued bits
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <termios.h>
int tcsendbreak(int fd, int duration);
DESCRIPTION
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).
| Interface | Attribute | Value |
| tcsendbreak () | Thread safety | MT-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).
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001.
SEE ALSO
| 2026-07-02 | Linux man-pages 6.19 |