tcflow(3C)						   Standard C Library Functions 						tcflow(3C)

NAME

       tcflow - suspend or restart the transmission or reception of data

SYNOPSIS

       #include <termios.h>

       int tcflow(int fildes, int action);

DESCRIPTION

       The tcflow() function suspends transmission or reception of data on the object referred to by fildes, depending on the value of action. The
       fildes argument is an open file descriptor associated with a terminal.

	 o  If action is TCOOFF, output is suspended.

	 o  If action is TCOON, suspended output is restarted.

	 o  If action is TCIOFF, the system transmits a STOP character, which is intended to cause the terminal device to stop	transmitting  data
	    to the system.

	 o  If	action is TCION, the system transmits a START character, which is intended to cause the terminal device to start transmitting data
	    to the system.

       The default on the opening of a terminal file is that neither its input nor its output are suspended.

       Attempts to use tcflow() from a process which is a member of a background process group on a fildes associated with its controlling  termi-
       nal,  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 tcflow() function will fail if:

       EBADF	       The fildes argument is not a valid file descriptor.

       EINVAL	       The action argument is not a supported value.

       ENOTTY	       The file associated with fildes is not a terminal.

       The tcflow() 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:

       +-----------------------------+-------------------------------+
       |      ATTRIBUTE TYPE	     |	     ATTRIBUTE VALUE	     |
       +-----------------------------+-------------------------------+
       |Interface Stability	     |Standard			     |
       +-----------------------------+-------------------------------+
       |MT-Level		     |MT-Safe, and Async-Signal-Safe |
       +-----------------------------+-------------------------------+

SEE ALSO

       tcsendbreak(3C), attributes(5), standards(5), termio(7I)

SunOS 5.10							    14 Aug 2002 							tcflow(3C)