luasocket/docs/dns.html

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<!-- dns ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

<h2 id="dns">DNS</h2>

<p>
IPv4 name resolution functions
<a href="#toip"><tt>dns.toip</tt></a>
and
<a href="#tohostname"><tt>dns.tohostname</tt></a>
return <em>all</em> information obtained from
the resolver in a table of the form:
</p>

<blockquote><tt>
resolved4 = {<br>
&nbsp;&nbsp;name = <i>canonic-name</i>,<br>
&nbsp;&nbsp;alias = <i>alias-list</i>,<br>
&nbsp;&nbsp;ip = <i>ip-address-list</i><br>
}
</tt> </blockquote>

<p>
Note that the <tt>alias</tt> list can be empty.
</p>

<p>
The more general name resolution function
<a href="#getaddrinfo"><tt>dns.getaddrinfo</tt></a>, which
supports both IPv6 and IPv4,
returns <em>all</em> information obtained from
the resolver in a table of the form:
</p>

<blockquote><tt>
resolved6 = {<br>
&nbsp;&nbsp;[1] = {<br>
&nbsp;&nbsp;&nbsp;&nbsp;family = <i>family-name-1</i>,<br>
&nbsp;&nbsp;&nbsp;&nbsp;addr = <i>address-1</i><br>
&nbsp;&nbsp;},<br>
&nbsp;&nbsp;...<br>
&nbsp;&nbsp;[n] = {<br>
&nbsp;&nbsp;&nbsp;&nbsp;family = <i>family-name-n</i>,<br>
&nbsp;&nbsp;&nbsp;&nbsp;addr = <i>address-n</i><br>
&nbsp;&nbsp;}<br>
}
</tt> </blockquote>

<p>
Here, <tt>family</tt> contains the string <tt>"inet"</tt> for IPv4
addresses, and <tt>"inet6"</tt> for IPv6 addresses.
</p>

<!-- getaddrinfo ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

<p class="name" id="getaddrinfo">
socket.dns.<b>getaddrinfo(</b>address<b>)</b>
</p>

<p class="description">
Converts from host name to address.
</p>

<p class="parameters">
<tt>Address</tt> can  be an IPv4 or IPv6 address or host name.
</p>

<p class="return">
The function returns a table with  all  information returned  by
the  resolver.  In  case of error, the function returns <b><tt>nil</tt></b>
followed by an error message.
</p>

<!-- gethostname ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

<p class="name" id="gethostname">
socket.dns.<b>gethostname()</b>
</p>

<p class="description">
Returns the standard host name for the machine as a string.
</p>

<!-- tohostname +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

<p class="name" id="tohostname">
socket.dns.<b>tohostname(</b>address<b>)</b>
</p>

<p class="description">
Converts from IPv4 address to host name.
</p>

<p class="parameters">
<tt>Address</tt> can  be an IP address  or host name.
</p>

<p class="return">
The function returns a string  with the canonic host name of the given
<tt>address</tt>, followed  by a  table with  all  information returned  by
the  resolver.  In  case of error, the function returns <b><tt>nil</tt></b>
followed by an error message.
</p>

<!-- toip +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

<p class="name" id="toip">
socket.dns.<b>toip(</b>address<b>)</b>
</p>

<p class="description">
Converts from host name to IPv4 address.
</p>

<p class="parameters">
<tt>Address</tt> can  be an IP address  or host name.
</p>

<p class="return">
Returns a string  with the first IP address  found for <tt>address</tt>,
followed  by a  table with  all  information returned  by the  resolver.
In  case of error, the function returns <b><tt>nil</tt></b> followed by an error
message.
</p>

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<small>
Last modified by Diego Nehab on <br>
Thu Apr 20 00:25:07 EDT 2006
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fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`"http://www.w3.org/TR/html4/strict.dtd">`
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More adjustments/bugfixes. 2004-06-21 08:07:58 +02:00			`<meta name="description" content="LuaSocket: DNS support">`
Added new instalation section to the manual. 2004-11-28 09:17:16 +01:00			`<meta name="keywords" content="Lua, LuaSocket, DNS, Network, Library, Support">`
More adjustments/bugfixes. 2004-06-21 08:07:58 +02:00			`<title>LuaSocket: DNS support</title>`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<link rel="stylesheet" href="reference.css" type="text/css">`
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fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<div class="header">`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<hr>`
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fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<tr><td align="center"><a href="http://www.lua.org">`
			`<img width="128" height="128" border="0" alt="LuaSocket" src="luasocket.png">`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</a></td></tr>`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<tr><td align="center" valign="top">Network support for the Lua language`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</td></tr>`
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fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="bar">`
Decent makefiles! 2009-05-27 11:31:38 +02:00			`<a href="index.html">home</a> ·`
			`<a href="index.html#download">download</a> ·`
Spell checked the manual. 2004-12-13 07:26:01 +01:00			`<a href="installation.html">installation</a> ·`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<a href="introduction.html">introduction</a> ·`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<a href="reference.html">reference</a>`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`
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			`<!-- dns ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<h2 id="dns">DNS</h2>`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00
			`<p>`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`IPv4 name resolution functions`
			`<a href="#toip"><tt>dns.toip</tt></a>`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`and`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<a href="#tohostname"><tt>dns.tohostname</tt></a>`
			`return <em>all</em> information obtained from`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`the resolver in a table of the form:`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

			`<blockquote><tt>`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`resolved4 = {<br>`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`  name = <i>canonic-name</i>,<br>`
			`  alias = <i>alias-list</i>,<br>`
			`  ip = <i>ip-address-list</i><br>`
			`}`
			`</tt> </blockquote>`

			`<p>`
			`Note that the <tt>alias</tt> list can be empty.`
			`</p>`

First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`<p>`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`The more general name resolution function`
			`<a href="#getaddrinfo"><tt>dns.getaddrinfo</tt></a>, which`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`supports both IPv6 and IPv4,`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`returns <em>all</em> information obtained from`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`the resolver in a table of the form:`
			`</p>`

			`<blockquote><tt>`
			`resolved6 = {<br>`
			`  [1] = {<br>`
			`    family = <i>family-name-1</i>,<br>`
			`    addr = <i>address-1</i><br>`
			`  },<br>`
			`  ...<br>`
			`  [n] = {<br>`
			`    family = <i>family-name-n</i>,<br>`
			`    addr = <i>address-n</i><br>`
			`  }<br>`
			`}`
			`</tt> </blockquote>`

			`<p>`
			`Here, <tt>family</tt> contains the string <tt>"inet"</tt> for IPv4`
			`addresses, and <tt>"inet6"</tt> for IPv6 addresses.`
			`</p>`

			`<!-- getaddrinfo ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="name" id="getaddrinfo">`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`socket.dns.<b>getaddrinfo(</b>address<b>)</b>`
			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="description">`
			`Converts from host name to address.`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="parameters">`
			`<tt>Address</tt> can be an IPv4 or IPv6 address or host name.`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="return">`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`The function returns a table with all information returned by`
			`the resolver. In case of error, the function returns <b><tt>nil</tt></b>`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`followed by an error message.`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`</p>`

Worked on the manual. Implemented stuffing (needs test) Added cddb and qp examples. 2004-02-04 15:29:11 +01:00			`<!-- gethostname ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="name" id="gethostname">`
Worked on the manual. Implemented stuffing (needs test) Added cddb and qp examples. 2004-02-04 15:29:11 +01:00			`socket.dns.<b>gethostname()</b>`
			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="description">`
			`Returns the standard host name for the machine as a string.`
Worked on the manual. Implemented stuffing (needs test) Added cddb and qp examples. 2004-02-04 15:29:11 +01:00			`</p>`

LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<!-- tohostname +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="name" id="tohostname">`
Almost done with manual... 2004-06-16 01:00:56 +02:00			`socket.dns.<b>tohostname(</b>address<b>)</b>`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="description">`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`Converts from IPv4 address to host name.`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="parameters">`
			`<tt>Address</tt> can be an IP address or host name.`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="return">`
Starting the manual. Oh well. 2004-05-25 08:51:43 +02:00			`The function returns a string with the canonic host name of the given`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<tt>address</tt>, followed by a table with all information returned by`
Working on the manual... Making better tests for error messages. Changed a few names. Moved gethostname to inet.c. 2004-01-24 03:47:24 +01:00			`the resolver. In case of error, the function returns <b><tt>nil</tt></b>`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`followed by an error message.`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

			`<!-- toip +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="name" id="toip">`
Almost done with manual... 2004-06-16 01:00:56 +02:00			`socket.dns.<b>toip(</b>address<b>)</b>`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="description">`
First stab at documenation Update Lua and Luasocket version in samples and in documentation Documented ipv5_v6only default option being set Documented tcp6 and udp6 Documented dns.getaddrinfo Documented zero-sized datagram change? Documented getoption 2012-04-16 19:15:26 +02:00			`Converts from host name to IPv4 address.`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="parameters">`
			`<tt>Address</tt> can be an IP address or host name.`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="return">`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`Returns a string with the first IP address found for <tt>address</tt>,`
			`followed by a table with all information returned by the resolver.`
Working on the manual... Making better tests for error messages. Changed a few names. Moved gethostname to inet.c. 2004-01-24 03:47:24 +01:00			`In case of error, the function returns <b><tt>nil</tt></b> followed by an error`
fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`message.`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`</p>`

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fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<div class="footer">`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<hr>`
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fix(docs) fix html linter issues in the docs (#358) 2022-03-22 19:21:58 +01:00			`<p class="bar">`
Decent makefiles! 2009-05-27 11:31:38 +02:00			`<a href="index.html">home</a> ·`
			`<a href="index.html#down">download</a> ·`
Spell checked the manual. 2004-12-13 07:26:01 +01:00			`<a href="installation.html">installation</a> ·`
LuaSocket 2.0 User's Manual. 2003-08-31 03:00:15 +02:00			`<a href="introduction.html">introduction</a> ·`
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			`Last modified by Diego Nehab on <br>`
Spell checked and updated modification date. 2006-04-20 06:27:13 +02:00			`Thu Apr 20 00:25:07 EDT 2006`
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