This module provides an interface to the POSIX calls for tty I/O
control. For a complete description of these calls, see the POSIX or
Unix manual pages. It is only available for those Unix versions
that support POSIX termios style tty I/O control (and then
only if configured at installation time).
All functions in this module take a file descriptor fd as their
first argument. This must be an integer file descriptor, such as
returned by sys.stdin.fileno().
This module should be used in conjunction with the
TERMIOS module, which defines the
relevant symbolic constants (see the next section).
The module defines the following functions:
- tcgetattr (fd)
-
Return a list containing the tty attributes for file descriptor
fd, as follows: [iflag, oflag, cflag,
lflag, ispeed, ospeed, cc] where
cc is a list of the tty special characters (each a string of
length 1, except the items with indices TERMIOS.VMIN and
TERMIOS.VTIME, which are integers when these fields are
defined). The interpretation of the flags and the speeds as well as
the indexing in the cc array must be done using the symbolic
constants defined in the TERMIOS module.
- tcsetattr (fd, when, attributes)
-
Set the tty attributes for file descriptor fd from the
attributes, which is a list like the one returned by
tcgetattr(). The when argument determines when the
attributes are changed: TERMIOS.TCSANOW to change
immediately, TERMIOS.TCSADRAIN to change after transmitting
all queued output, or TERMIOS.TCSAFLUSH to change after
transmitting all queued output and discarding all queued input.
- tcsendbreak (fd, duration)
-
Send a break on file descriptor fd. A zero duration sends
a break for 0.25-0.5 seconds; a nonzero duration has a system
dependent meaning.
- tcdrain (fd)
-
Wait until all output written to file descriptor fd has been
transmitted.
- tcflush (fd, queue)
-
Discard queued data on file descriptor fd. The queue
selector specifies which queue: TERMIOS.TCIFLUSH for the
input queue, TERMIOS.TCOFLUSH for the output queue, or
TERMIOS.TCIOFLUSH for both queues.
- tcflow (fd, action)
-
Suspend or resume input or output on file descriptor fd. The
action argument can be TERMIOS.TCOOFF to suspend
output, TERMIOS.TCOON to restart output,
TERMIOS.TCIOFF to suspend input, or
TERMIOS.TCION to restart input.