tcflow(3) [osf1 man page]

tcflow(3)						     Library Functions Manual							 tcflow(3)

NAME

       tcflow -  Performs flow control functions

LIBRARY

       Standard C Library (libc.so, libc.a)

SYNOPSIS

       #include <termios.h>

       int tcflow(
	       int filedes,
	       int action);

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       tcflow():  XPG4, XPG4-UNIX

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

PARAMETERS

       Specifies  an open file descriptor.  Specifies one of the following: Suspend output.  Restart suspended output.	Transmit a STOP character,
       which is intended to cause the terminal device to stop transmitting data to the system.	Transmit a START character, which is  intended	to
       cause the terminal device to start transmitting data to the system.

DESCRIPTION

       The tcflow() function suspends transmission or reception of data on the object referred to by the filedes parameter, depending on the value
       of the action parameter.

       A process group is sent a SIGTTOU signal if the tcflow() function is called from one of its member processes.  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, a value of 0 (zero) is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error.

ERRORS

       The tcflow() function sets errno to the specified values for the following conditions:

       The  filedes  parameter does not specify a valid file descriptor.  The action parameter is not a supported value.  The file associated with
       the filedes parameter is not a terminal.

RELATED INFORMATION

       Functions: tcdrain(3), tcflush(3), tcsendbreak(3)

       Files: termios(4)

       Standards: standards(5) delim off

																	 tcflow(3)

TCSENDBREAK(3)						   BSD Library Functions Manual 					    TCSENDBREAK(3)

NAME

     tcsendbreak, tcdrain, tcflush, tcflow -- line control functions

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <termios.h>

     int
     tcdrain(int fd);

     int
     tcflow(int fd, int action);

     int
     tcflush(int fd, int action);

     int
     tcsendbreak(int fd, int len);

DESCRIPTION

     The tcdrain function waits until all output written to the terminal referenced by fd has been transmitted to the terminal.

     The tcflow function suspends transmission of data to or the reception of data from the terminal referenced by fd depending on the value of
     action.  The value of action must be one of the following:

     TCOOFF  Suspend output.

     TCOON   Restart suspended output.

     TCIOFF  Transmit a STOP character, which is intended to cause the terminal to stop transmitting data to the system.  (See the description of
	     IXOFF in the 'Input Modes' section of termios(4)).

     TCION   Transmit a START character, which is intended to cause the terminal to start transmitting data to the system.  (See the description
	     of IXOFF in the 'Input Modes' section of termios(4)).

     The tcflush function discards any data written to the terminal referenced by fd which has not been transmitted to the terminal, or any data
     received from the terminal but not yet read, depending on the value of action.  The value of action must be one of the following:

     TCIFLUSH	Flush data received but not read.

     TCOFLUSH	Flush data written but not transmitted.

     TCIOFLUSH	Flush both data received but not read and data written but not transmitted.

     The tcsendbreak function transmits a continuous stream of zero-valued bits for four-tenths of a second to the terminal referenced by fd.  The
     len parameter is ignored in this implementation.

RETURN VALUES

     Upon successful completion, all of these functions return a value of zero.

ERRORS

     If any error occurs, a value of -1 is returned and the global variable errno is set to indicate the error, as follows:

     [EBADF]		The fd argument is not a valid file descriptor.

     [EINVAL]		The action argument is not a proper value.

     [ENOTTY]		The file associated with fd is not a terminal.

     [EINTR]		A signal interrupted the tcdrain function.

SEE ALSO

     tcsetattr(3), termios(4)

STANDARDS

     The tcsendbreak, tcdrain, tcflush and tcflow functions are expected to be compliant with the IEEE Std 1003.1-1988 (``POSIX.1'') specifica-
     tion.

BSD
								   June 4, 1993 							       BSD