The readline module defines a number of functions used either
directly or from the rlcompleter module to facilitate
completion and history file read and write from the Python
interpreter.
The readline module defines the following functions:
Set the number of lines to save in the history file.
write_history_file() uses this value to truncate the
history file when saving. Negative values imply unlimited history
file size.
Set or remove the startup_hook function. If function is specified,
it will be used as the new startup_hook function; if omitted or
None, any hook function already installed is removed. The
startup_hook function is called with no arguments just
before readline prints the first prompt.
Set or remove the pre_input_hook function. If function is specified,
it will be used as the new pre_input_hook function; if omitted or
None, any hook function already installed is removed. The
pre_input_hook function is called with no arguments after the first prompt
has been printed and just before readline starts reading input characters.
Set or remove the completer function. If function is specified,
it will be used as the new completer function; if omitted or
None, any completer function already installed is removed. The
completer function is called as function(text,
state), for state in 0, 1, 2, ...,
until it returns a non-string value. It should return the next
possible completion starting with text.