LookupIP 1.01

	      Copyright (C) 1998-2001 by Carsten Clasohm
		   http://www.clasohm.com/lookupip/


Introduction
============

LookupIP is a Windows tool for replacing numerical IP addresses by the
host's domain name (like 198.3.103.72 -> snare.excite.com). It is
mainly intended for webmasters who are looking for a fast and
convenient way to process the logfiles of their Web servers.

I know that there already are a couple of programs which claim to do
just that. But either they were too slow for my taste, or they cost
money. LookupIP is small, as fast as your network connection allows,
it is free, and the source code is included!


Usage
=====

LookupIP has no graphical UI. Though it is invoked from Window's
command prompt, it is a real 32-bit application, not a DOS program.


  LookupIP [options] [input file] [output file]

  Options:
    -t <thread count>  Max. count of concurrent DNS lookups (default: 20)
    -a <days>          Max. age of stored DNS data (default: 90 days)
    -u <days>          Max. age for unknown hosts (default: 14 days)
    -v                 Increase verbousness


The program uses threads to concurrently look up multiple IP
addresses. The faster your network connection, the more threads you
can use. (But don't overdo it - most name servers are quite busy.)

The next two parameters control LookupIP's DNS cache. All host names
are stored in the file dns.txt in the same directory where
LookupIP.exe resides. By default, a cache entry is deleted 90 days
after the lookup. If the lookup failed, it is deleted after 14 days.
(Failed lookups can be caused by a temporary or permanent DNS
configuration error, or because the address owner does not allow
reverse lookups.)

Both filename parameters are optional. If both are present, input is
read from the first and the converted output written to the second
file. If only one is supplied, it is used as the input source, while
the output is sent to the console. If no filename is given, input is
read from the console, and output written to it. This is intended for
input/output redirection using "<", ">" and "|".


Updates
=======

The most current version of LookupIP can be found at

    http://www.clasohm.com/lookupip/

Questions about the current and suggestions for future versions should
be sent to

    support@clasohm.com


License
=======

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at
your option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
USA.