mirror of
https://github.com/reactos/reactos.git
synced 2024-11-10 00:34:39 +00:00
222 lines
8.1 KiB
HTML
222 lines
8.1 KiB
HTML
<html>
|
|
<head>
|
|
<title>adns - advanced, alternative, asynchronous resolver</title>
|
|
<link rev="made" href="mailto:adns-maint@chiark.greenend.org.uk">
|
|
</head>
|
|
<body>
|
|
<h1>GNU adns</h1>
|
|
|
|
<strong>Advanced, easy to use, asynchronous-capable DNS client
|
|
library and utilities.</strong>
|
|
|
|
<!-- Note: this file is maintained in Ian Jackson's private CVS. -->
|
|
<!-- -->
|
|
<!-- It is served on the GNU site and also from my own system, -->
|
|
<!-- under the URL http://www.chiark.greenend.org.uk/adns/ -->
|
|
<!-- Please ensure that all links continine to be correct -->
|
|
<!-- both for www.gnu.org and chiark. -->
|
|
<!-- -->
|
|
<!-- $Id$ -->
|
|
|
|
<p>
|
|
|
|
adns is a resolver library for C (and C++) programs, and a collection
|
|
of useful DNS resolver utilities.
|
|
|
|
|
|
<h2>C library</h2>
|
|
|
|
In contrast with the standard interfaces, gethostbyname et al and
|
|
libresolv, it has the following features:
|
|
|
|
<ul>
|
|
|
|
<li>It is reasonably easy to use for simple programs which just want
|
|
to translate names to addresses, look up MX records, etc.
|
|
|
|
<li>It can be used in an asynchronous, non-blocking, manner. Many
|
|
queries can be handled simultaneously.
|
|
|
|
<li>Responses are decoded automatically into a natural representation
|
|
for a C program - there is no need to deal with DNS packet formats.
|
|
|
|
<li>Sanity checking (eg, name syntax checking, reverse/forward
|
|
correspondence, CNAME pointing to CNAME) is performed automatically.
|
|
|
|
<li>Time-to-live, CNAME and other similar information is returned in
|
|
an easy-to-use form, without getting in the way.
|
|
|
|
<li>There is no global state in the library; resolver state is an
|
|
opaque data structure which the client creates explicitly. A program
|
|
can have several instances of the resolver.
|
|
|
|
<li>Errors are reported to the application in a way that distinguishes
|
|
the various causes of failure properly.
|
|
|
|
<li>Understands conventional resolv.conf, but this can overridden by
|
|
environment variables.
|
|
|
|
<li>Flexibility. For example, the application can tell adns to:
|
|
ignore environment variables (for setuid programs), disable hostname
|
|
syntax sanity checks to return arbitrary data, override or ignore
|
|
resolv.conf in favour of supplied configuration, etc.
|
|
|
|
<li>Believed to be correct ! For example, will correctly back off to
|
|
TCP in case of long replies or queries, or to other nameservers if
|
|
several are available. It has sensible handling of bad responses etc.
|
|
|
|
</ul>
|
|
|
|
<h2>DNS utility programs</h2>
|
|
|
|
adns also comes with a number of utility programs for use from the
|
|
command line and in scripts:
|
|
|
|
<ul>
|
|
|
|
<li><code>adnslogres</code> is a much faster version of Apache's
|
|
logresolv program.
|
|
|
|
<li><code>adnsresfilter</code> is a filter which copies its input to
|
|
its output, replacing IP addresses by the corresponding names, without
|
|
unduly delaying the output. For example, you can usefully pipe the
|
|
output of netstat -n, tcpdump -ln, and the like, into it.
|
|
|
|
<li><code>adnshost</code> is a general-purpose DNS lookup utility
|
|
which can be used easily in from the command line and from shell
|
|
scripts to do simple lookups. In a more advanced mode it can be used
|
|
as a general-purpose DNS helper program for scripting languages which
|
|
can invoke and communicate with subprocesses. See the
|
|
<A href="http://www.chiark.greenend.org.uk/~ian/adns/adnshost.txt">adnshost
|
|
usage message</A> for a summary of its capabilities.
|
|
|
|
</ul>
|
|
|
|
<h2>Documentation</h2>
|
|
|
|
I'm afraid there is no manual yet. However, competent C programmers
|
|
should be able to use the library based on the
|
|
<A href="http://www.chiark.greenend.org.uk/~ian/adns/adns.h.txt">commented
|
|
adns.h header file</A>, and the usage messages for the programs should
|
|
be sufficient.
|
|
|
|
<h2>Feedback</h2>
|
|
|
|
I'd be pleased if you would let me know if you're using my library in
|
|
your project, and what you think of it.
|
|
|
|
<p>
|
|
|
|
If you are subscribed to <code>adns-discuss</code> please send
|
|
feedback, including bug reports, there; otherwise send mail to
|
|
<code>adns-bugreports@chiark.greenend.org.uk</code>. If you'd prefer
|
|
that your message wasn't forwarded to the <code>adns-bugreports</code>
|
|
list, send it to <code>adns-maint@chiark.greenend.org.uk</code>.
|
|
|
|
<h2>Mailinglists</h2>
|
|
|
|
I have set up mailinglists <code>adns-announce</code> and
|
|
<code>adns-discuss</code>. The announcements list is moderated and
|
|
will contain only announcements of important bugs, new versions, etc.
|
|
The bug reports address mentioned above is also a mailing list; feel
|
|
free to subscribe to it.
|
|
|
|
<p>
|
|
|
|
There are
|
|
<A href="http://www.chiark.greenend.org.uk/mailman/listinfo">archives
|
|
and subscription web pages</A>, or you can subscribe by sending mail
|
|
containing the word `subscribe' to
|
|
<code>adns-announce-REQUEST@chiark.greenend.org.uk</code> or
|
|
<code>adns-discuss-REQUEST@chiark.greenend.org.uk</code>.
|
|
|
|
<h2>Download</h2>
|
|
|
|
Available for download from
|
|
<A href="http://www.chiark.greenend.org.uk/~ian/adns/">chiark.greenend.org.uk</A>
|
|
are:
|
|
<ul>
|
|
<li>The <A href="http://www.chiark.greenend.org.uk/~ian/adns/adns.tar.gz">current
|
|
release</A> as a gzipped tarfile.
|
|
<li><A href="http://www.chiark.greenend.org.uk/~ian/adns/adns.h.txt">adns.h</A>
|
|
API header file with comments, and
|
|
<A href="http://www.chiark.greenend.org.uk/~ian/adns/adnshost.txt">usage
|
|
message for adnshost</A> (currently there is no manual, sorry).
|
|
<li>All versions released so far are also available via
|
|
<A href="ftp://ftp.chiark.greenend.org.uk/users/ian/adns/">anonymous
|
|
FTP</A> and <A href="http://www.chiark.greenend.org.uk/~ian/adns/ftp/">HTTP</A>,
|
|
<li>A mirror of my CVS repository is available via rsync from
|
|
<code>rsync.chiark.greenend.org.uk::ftp/users/ian/cvs-pub/adns</code>
|
|
(use FTP first to find your way around), or via
|
|
<A href="http://www.chiark.greenend.org.uk/ucgi/~ijackson/cvsweb/adns/">cvsweb</A>.
|
|
</ul>
|
|
|
|
adns is also available from the
|
|
<A href="http://www.gnu.org/">GNU Project</A> FTP servers and their
|
|
<A href="http://www.gnu.org/order/ftp.html">mirrors</A>.
|
|
|
|
<h2>Technical note</h2>
|
|
|
|
adns requires a real nameserver like
|
|
<A href="http://www.isc.org/view.cgi?/products/BIND/index.phtml">BIND</A>
|
|
or
|
|
<A href="http://www.dents.org/">Dents</A> running on
|
|
the same system or a nearby one, which must be willing to provide
|
|
`recursive service'. I.e., adns is a `stub resolver'. All properly
|
|
configured UN*X and GNU systems will already have such nameserver(s);
|
|
they are usually listed in /etc/resolv.conf.
|
|
|
|
<h2>Copyright and licensing</h2>
|
|
|
|
<kbd>adns</kbd> is Copyright 1997-2000 Ian Jackson, Copyright
|
|
1999-2000 Tony Finch, and Copyright (C) 1991 Massachusetts Institute
|
|
of Technology.
|
|
|
|
<p>
|
|
|
|
<kbd>adns</kbd> 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.
|
|
|
|
<p>
|
|
|
|
This program and documentation is distributed in the hope that it will
|
|
be useful, but <em>without any warranty</em>; without even the implied
|
|
warranty of <em>merchantability</em> or <em>fitness for a particular
|
|
purpose</em>. See the
|
|
<A href="http://www.chiark.greenend.org.uk/~ian/COPYING.txt">GNU
|
|
General Public License</A> for more details.
|
|
|
|
<p>
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with <kbd>adns</kbd>, or one should be available above; if not,
|
|
write to the
|
|
<A href="http://www.fsf.org/">Free Software Foundation</A>,
|
|
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA,
|
|
or email <code>adns-maint@chiark.greenend.org.uk</code>.
|
|
|
|
<p>
|
|
|
|
<hr>
|
|
<A href="http://www.chiark.greenend.org.uk/">Ian Jackson</A> /
|
|
<A href="mailto:adns-maint@chiark.greenend.org.uk"><tt>adns-maint@chiark.greenend.org.uk</tt></A>;
|
|
more <A href="http://www.chiark.greenend.org.uk/~ian/software/">free
|
|
software</A> by me.
|
|
<p>
|
|
|
|
<A href="http://www.gnu.org/">GNU home page</A>;
|
|
<A href="http://www.chiark.greenend.org.uk/">chiark home page</A>;
|
|
<A href="/">site or mirror home page</A>
|
|
<p>
|
|
|
|
This web page is Copyright (C)1996-2000 Ian Jackson. See the
|
|
<A href="http://www.chiark.greenend.org.uk/~ian/sw-www-copy.html">Copyright/acknowledgements</A>.
|
|
<p>
|
|
|
|
Use any browser -
|
|
<A href="http://www.anybrowser.org/campaign/">Campaign for a non-browser-specific WWW</A>
|
|
|
|
</body>
|
|
</html>
|