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<H2><A NAME="SECTION0092010000000000000000"></A><A NAME="readline-example"></A>
<BR>
7.20.1 Example
</H2>

<P>
The following example demonstrates how to use the
<tt class="module">readline</tt> module's history reading and writing functions to
automatically load and save a history file named <span class="file">.pyhist</span> from
the user's home directory.  The code below would normally be executed
automatically during interactive sessions from the user's
<a class="envvar" id='l2h-2964' xml:id='l2h-2964'>PYTHONSTARTUP</a> file.

<P>
<div class="verbatim"><pre>
import os
histfile = os.path.join(os.environ["HOME"], ".pyhist")
try:
    readline.read_history_file(histfile)
except IOError:
    pass
import atexit
atexit.register(readline.write_history_file, histfile)
del os, histfile
</pre></div>

<P>
The following example extends the <tt class="class">code.InteractiveConsole</tt> class to
support history save/restore.

<P>
<div class="verbatim"><pre>
import code
import readline
import atexit
import os

class HistoryConsole(code.InteractiveConsole):
    def __init__(self, locals=None, filename="&lt;console&gt;",
                 histfile=os.path.expanduser("~/.console-history")):
        code.InteractiveConsole.__init__(self)
        self.init_history(histfile)

    def init_history(self, histfile):
        readline.parse_and_bind("tab: complete")
        if hasattr(readline, "read_history_file"):
            try:
                readline.read_history_file(histfile)
            except IOError:
                pass
            atexit.register(self.save_history, histfile)

    def save_history(self, histfile):
        readline.write_history_file(histfile)
</pre></div>

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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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