Name: logviewer.py
Author: Victor Trac (victor.trac@gmail.com)

Overview
------------
logviewer.py is an extension of Python's included SimpleHTTPServer.py that adds
several additional features:
1. It accepts an optional run-time parameter that specifies a local directory 
   from which to serve files.
2. It accepts an optional integer URL parameter that will only send the last
   specified number of lines.
3. It will send a HTTP 1.1 keepalive header and will continually stream the 
   file as it is being updated on the file system.

Usage
-----
Starting:
    $ python /path/to/logviewer.py 8080 /var/log/mylogs

This will launch a Python process, listening on port 8080 that will serve a 
directory listing of /var/log/mylogs on request. When someone clicks a file in
that directory listing in a browser, logviewer.py will serve the entire file
while keeping the connection open to append to the log, just like 'tail -f'. 

Additionally, a HTTP request can include a "?n" parameter, where n is an integer
that will display the last n number of lines of the file.  Example:

http://1.2.3.4:8080/mylog.log?50

This will send the last 50 lines of mylog.log and then continue to update it as
it is being appended.