NAME

tcsendbreak − send a “break” for a specific duration

SYNOPSIS

#include <termios.h>

int tcsendbreak(int fildes, int duration);

DESCRIPTION

The fildes argument is an open file descriptor associated with a terminal. 

If the terminal is using asynchronous serial data transmission, tcsendbreak() will cause transmission of a continuous stream of zero-valued bits for a specific duration.  If duration is 0, it will cause transmission of zero-valued bits for at least 0.25 seconds, and not more than 0.5 seconds.  If duration is not 0, it behaves in a way similar to tcdrain(3). 

If the terminal is not using asynchronous serial data transmission, it sends data to generate a break condition or returns without taking any action. 

Attempts to use tcsendbreak() from a process which is a member of a background process group on a fildes associated with its controlling terminal will cause the process group to be sent a SIGTTOU signal.  If the calling process is blocking or ignoring SIGTTOU signals, the process is allowed to perform the operation, and no signal is sent. 

RETURN VALUES

Upon successful completion, 0 is returned. Otherwise, −1 is returned and errno is set to indicate the error. 

ERRORS

The tcsendbreak() function will fail if:

EBADF The fildes argument is not a valid file descriptor. 

ENOTTY The file associated with fildes is not a terminal. 

The tcsendbreak() function may fail if:

EIO The process group of the writing process is orphaned, and the writing process is not ignoring or blocking SIGTTOU. 

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

SEE ALSO

tcdrain(3), attributes(5), termio(7I)

SunOS 5.6  —  Last change: 29 Dec 1996