tcflow() -- termios Macro (termios.h)

Control flow on a terminal device
#include <termios.h>
int tcflow(fd, action)
int fd;
int action;

The termios macro tcflow()  suspends transmission of data to, or receiption
of data from,  the device described by file descriptor  fd. When a terminal
device is opened, by default neither its input nor its output is suspended.
action gives the action to take, as follows:

TCOOFF
     Suspend output.

TCOON
     Restart output.

TCIOFF
     Transmit character STOP,
      which tells the terminal to stop sending data to the system.

TCION
     Transmit character  START, which tells the  terminal to resume sending
     data to the system.

These constants are defined in header file <termios.h>.

Should all  go well,  tcflow() returns zero.   If something goes  wrong, it
returns -1 and sets errno to an appropriate value, as follows:

EBADF
     fd is not a valid file descriptor.

EINVAL
     action is not set to an appropriate value.

ENOTTY
     fd does not describe a terminal device.

See Also

termios
POSIX Standard, §7.2.2

© 2012 by Stephen A. Ness