luasocket-2.0.2/doc/udp.html - nest-learning-thermostat/5.1.7/luasocket - Git at Google

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 <!-- udp ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <h2 id=udp>UDP</h2>

 <!-- socket.udp ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

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

 <p class="description">
 Creates and returns an unconnected UDP object. Unconnected objects support the
 <a href="#sendto"><tt>sendto</tt></a>,
 <a href="#receive"><tt>receive</tt></a>,
 <a href="#receivefrom"><tt>receivefrom</tt></a>,
 <a href="#getsockname"><tt>getsockname</tt></a>,
 <a href="#setoption"><tt>setoption</tt></a>,
 <a href="#settimeout"><tt>settimeout</tt></a>,
 <a href="#setpeername"><tt>setpeername</tt></a>,
 <a href="#setsockname"><tt>setsockname</tt></a>, and
 <a href="#close"><tt>close</tt></a>.
 The <a href="#setpeername"><tt>setpeername</tt></a>
 is used to connect the object.
 </p>

 <p class="return">
 In case of success, a new unconnected UDP object
 returned. In case of error, <b><tt>nil</tt></b> is returned, followed by
 an error message.
 </p>

 <!-- close +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="close">
 connected:<b>close()</b><br>
 unconnected:<b>close()</b>
 </p>

 <p class="description">
 Closes a UDP object. The internal socket
 used by the object is closed and the local address to which the
 object was bound is made available to other applications. No
 further operations (except for further calls to the <tt>close</tt>
 method) are allowed on a closed socket.
 </p>

 <p class="note">
 Note: It is important to close all used sockets
 once they are not needed, since, in many systems, each socket uses
 a file descriptor, which are limited system resources.
 Garbage-collected objects are automatically closed before
 destruction, though.
 </p>

 <!-- getpeername +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="getpeername">
 connected:<b>getpeername()</b>
 </p>

 <p class="description">
 Retrieves information about the peer
 associated with a connected UDP object.
 </p>

 <p class="return">
 Returns the IP address and port number of the peer.
 </p>

 <p class="note">
 Note: It makes no sense to call this method on unconnected objects.
 </p>

 <!-- getsockname +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="getsockname">
 connected:<b>getsockname()</b><br>
 unconnected:<b>getsockname()</b>
 </p>

 <p class="description">
 Returns the local address information associated to the object.
 </p>

 <p class="return">
 The method returns a string with local IP
 address and a number with the port. In case of error, the method
 returns <b><tt>nil</tt></b>.
 </p>

 <p class="note">
 Note: UDP sockets are not bound to any address
 until the <a href="#setsockname"><tt>setsockname</tt></a> or the
 <a href="#sendto"><tt>sendto</tt></a> method is called for the
 first time (in which case it is bound to an ephemeral port and the
 wild-card address).
 </p>

 <!-- receive +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="receive">
 connected:<b>receive(</b>[size]<b>)</b><br>
 unconnected:<b>receive(</b>[size]<b>)</b>
 </p>

 <p class="description">
 Receives a datagram from the UDP object. If
 the UDP object is connected, only datagrams coming from the peer
 are accepted. Otherwise, the returned datagram can come from any
 host.
 </p>

 <p class="parameters">
 The optional <tt>size</tt> parameter
 specifies the maximum size of the datagram to be retrieved. If
 there are more than <tt>size</tt> bytes available in the datagram,
 the excess bytes are discarded. If there are less then
 <tt>size</tt> bytes available in the current datagram, the
 available bytes are returned. If <tt>size</tt> is omitted, the
 maximum datagram size is used (which is currently limited by the
 implementation to 8192 bytes).
 </p>

 <p class="return">
 In case of success, the method returns the
 received datagram. In case of timeout, the method returns
 <b><tt>nil</tt></b> followed by the string '<tt>timeout</tt>'.
 </p>

 <!-- receivefrom +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="receivefrom">
 unconnected:<b>receivefrom(</b>[size]<b>)</b>
 </p>

 <p class="description">
 Works exactly as the <a href="#receive"><tt>receive</tt></a>
 method, except it returns the IP
 address and port as extra return values (and is therefore slightly less
 efficient).
 </p>

 <!-- send ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="send">
 connected:<b>send(</b>datagram<b>)</b>
 </p>

 <p class="description">
 Sends a datagram to the UDP peer of a connected object.
 </p>

 <p class="parameters">
 <tt>Datagram</tt> is a string with the datagram contents.
 The maximum datagram size for UDP is 64K minus IP layer overhead.
 However datagrams larger than the link layer packet size will be
 fragmented, which may deteriorate performance and/or reliability.
 </p>

 <p class="return">
 If successful, the method returns 1. In case of
 error, the method returns <b><tt>nil</tt></b> followed by an error message.
 </p>

 <p class="note">
 Note: In UDP, the <tt>send</tt> method never blocks
 and the only way it can fail is if the underlying transport layer
 refuses to send a message to the specified address (i.e. no
 interface accepts the address).
 </p>

 <!-- sendto ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="sendto">
 unconnected:<b>sendto(</b>datagram, ip, port<b>)</b>
 </p>

 <p class="description">
 Sends a datagram to the specified IP address and port number.
 </p>

 <p class="parameters">
 <tt>Datagram</tt> is a string with the
 datagram contents.
 The maximum datagram size for UDP is 64K minus IP layer overhead.
 However datagrams larger than the link layer packet size will be
 fragmented, which may deteriorate performance and/or reliability.
 <tt>Ip</tt> is the IP address of the recipient.
 Host names are <em>not</em> allowed for performance reasons.

 <tt>Port</tt> is the port number at the recipient.
 </p>

 <p class="return">
 If successful, the method returns 1. In case of
 error, the method returns <b><tt>nil</tt></b> followed by an error message.
 </p>

 <p class="note">
 Note: In UDP, the <tt>send</tt> method never blocks
 and the only way it can fail is if the underlying transport layer
 refuses to send a message to the specified address (i.e. no
 interface accepts the address).
 </p>

 <!-- setpeername +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="setpeername">
 connected:<b>setpeername(</b>'*'<b>)</b><br>
 unconnected:<b>setpeername(</b>address, port<b>)</b>
 </p>

 <p class="description">
 Changes the peer of a UDP object. This
 method turns an unconnected UDP object into a connected UDP
 object or vice versa.
 </p>

 <p class="description">
 For connected objects, outgoing datagrams
 will be sent to the specified peer, and datagrams received from
 other peers will be discarded by the OS. Connected UDP objects must
 use the <a href="#send"><tt>send</tt></a> and
 <a href="#receive"><tt>receive</tt></a> methods instead of
 <a href="#sendto"><tt>sendto</tt></a> and
 <a href="#receivefrom"><tt>receivefrom</tt></a>.
 </p>

 <p class="parameters">
 <tt>Address</tt> can be an IP address or a
 host name. <tt>Port</tt> is the port number. If <tt>address</tt> is
 '<tt>*</tt>' and the object is connected, the peer association is
 removed and the object becomes an unconnected object again. In that
 case, the <tt>port</tt> argument is ignored.
 </p>

 <p class="return">
 In case of error the method returns
 <b><tt>nil</tt></b> followed by an error message. In case of success, the
 method returns 1.
 </p>

 <p class="note">
 Note: Since the address of the peer does not have
 to be passed to and from the OS, the use of connected UDP objects
 is recommended when the same peer is used for several transmissions
 and can result in up to 30% performance gains.
 </p>

 <!-- setsockname +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="setsockname">
 unconnected:<b>setsockname(</b>address, port<b>)</b>
 </p>

 <p class="description">
 Binds the UDP object to a local address.
 </p>

 <p class="parameters">
 <tt>Address</tt> can be an IP address or a
 host name. If <tt>address</tt> is '<tt>*</tt>' the system binds to
 all local interfaces using the constant <tt>INADDR_ANY</tt>. If
 <tt>port</tt> is 0, the system chooses an ephemeral port.
 </p>

 <p class="return">
 If successful, the method returns 1. In case of
 error, the method returns <b><tt>nil</tt></b> followed by an error
 message.
 </p>

 <p class="note">
 Note: This method can only be called before any
 datagram is sent through the UDP object, and only once. Otherwise,
 the system automatically binds the object to all local interfaces
 and chooses an ephemeral port as soon as the first datagram is
 sent. After the local address is set, either automatically by the
 system or explicitly by <tt>setsockname</tt>, it cannot be
 changed.
 </p>

 <!-- setoption +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="setoption">
 connected:<b>setoption(</b>option [, value]<b>)</b><br>
 unconnected:<b>setoption(</b>option [, value]<b>)</b>
 </p>

 <p class="description">
 Sets options for the UDP object. Options are
 only needed by low-level or time-critical applications. You should
 only modify an option if you are sure you need it.</p>
 <p class="parameters"><tt>Option</tt> is a string with the option
 name, and <tt>value</tt> depends on the option being set:
 </p>

 <ul>
 <li>'<tt>dontroute</tt>': Setting this option to <tt>true</tt>
 indicates that outgoing messages should bypass the standard routing
 facilities;</li>
 <li>'<tt>broadcast</tt>': Setting this option to <tt>true</tt>
 requests permission to send broadcast datagrams on the
 socket.</li>
 </ul>

 <p class="return">
 The method returns 1 in case of success, or
 <b><tt>nil</tt></b> followed by an error message otherwise.
 </p>

 <p class="note">
 Note: The descriptions above come from the man
 pages.
 </p>

 <!-- settimeout +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

 <p class="name" id="settimeout">
 connected:<b>settimeout(</b>value<b>)</b><br>
 unconnected:<b>settimeout(</b>value<b>)</b>
 </p>

 <p class="description">
 Changes the timeout values for the object.  By default, the
 <a href="#receive"><tt>receive</tt></a> and
 <a href="#receivefrom"><tt>receivefrom</tt></a>
 operations are blocking. That is, any call to the methods will block
 indefinitely, until data arrives.  The <tt>settimeout</tt> function defines
 a limit on the amount of time the functions can block. When a timeout is
 set and the specified amount of time has elapsed, the affected methods
 give up and fail with an error code.
 </p>

 <p class="parameters">
 The amount of time to wait is specified as
 the <tt>value</tt> parameter, in seconds. The <b><tt>nil</tt></b> timeout
 <tt>value</tt> allows operations to block indefinitely. Negative
 timeout values have the same effect.
 </p>

 <p class="note">
 Note: In UDP, the <a href="#send"><tt>send</tt></a>
 and <a href="#sentdo"><tt>sendto</tt></a> methods never block (the
 datagram is just passed to the OS and the call returns
 immediately). Therefore, the <tt>settimeout</tt> method has no
 effect on them.
 </p>

 <p class="note">
 Note: The old <tt>timeout</tt> method is
 deprecated. The name has been changed for sake of uniformity, since
 all other method names already contained verbs making their
 imperative nature obvious.
 </p>

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 <small>
 Last modified by Diego Nehab on <br>
 Thu Apr 20 00:26:01 EDT 2006
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	"http://www.w3.org/TR/html4/strict.dtd">
	<html>

	<head>
	<meta name="description" content="LuaSocket: The UDP support">
	<meta name="keywords" content="Lua, LuaSocket, Socket, UDP, Library, Network, Support">
	<title>LuaSocket: UDP support</title>
	<link rel="stylesheet" href="reference.css" type="text/css">
	</head>

	<body>

	<!-- header ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<div class=header>
	<hr>
	<center>
	<table summary="LuaSocket logo">
	<tr><td align=center><a href="http://www.lua.org">
	<img width=128 height=128 border=0 alt="LuaSocket" src="luasocket.png">
	</a></td></tr>
	<tr><td align=center valign=top>Network support for the Lua language
	</td></tr>
	</table>
	<p class=bar>
	<a href="home.html">home</a> ·
	<a href="home.html#download">download</a> ·
	<a href="installation.html">installation</a> ·
	<a href="introduction.html">introduction</a> ·
	<a href="reference.html">reference</a>
	</p>
	</center>
	<hr>
	</div>


	<!-- udp ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<h2 id=udp>UDP</h2>

	<!-- socket.udp ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

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

	<p class="description">
	Creates and returns an unconnected UDP object. Unconnected objects support the
	<a href="#sendto"><tt>sendto</tt></a>,
	<a href="#receive"><tt>receive</tt></a>,
	<a href="#receivefrom"><tt>receivefrom</tt></a>,
	<a href="#getsockname"><tt>getsockname</tt></a>,
	<a href="#setoption"><tt>setoption</tt></a>,
	<a href="#settimeout"><tt>settimeout</tt></a>,
	<a href="#setpeername"><tt>setpeername</tt></a>,
	<a href="#setsockname"><tt>setsockname</tt></a>, and
	<a href="#close"><tt>close</tt></a>.
	The <a href="#setpeername"><tt>setpeername</tt></a>
	is used to connect the object.
	</p>

	<p class="return">
	In case of success, a new unconnected UDP object
	returned. In case of error, <b><tt>nil</tt></b> is returned, followed by
	an error message.
	</p>

	<!-- close +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="close">
	connected:<b>close()</b><br>
	unconnected:<b>close()</b>
	</p>

	<p class="description">
	Closes a UDP object. The internal socket
	used by the object is closed and the local address to which the
	object was bound is made available to other applications. No
	further operations (except for further calls to the <tt>close</tt>
	method) are allowed on a closed socket.
	</p>

	<p class="note">
	Note: It is important to close all used sockets
	once they are not needed, since, in many systems, each socket uses
	a file descriptor, which are limited system resources.
	Garbage-collected objects are automatically closed before
	destruction, though.
	</p>

	<!-- getpeername +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="getpeername">
	connected:<b>getpeername()</b>
	</p>

	<p class="description">
	Retrieves information about the peer
	associated with a connected UDP object.
	</p>

	<p class="return">
	Returns the IP address and port number of the peer.
	</p>

	<p class="note">
	Note: It makes no sense to call this method on unconnected objects.
	</p>

	<!-- getsockname +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="getsockname">
	connected:<b>getsockname()</b><br>
	unconnected:<b>getsockname()</b>
	</p>

	<p class="description">
	Returns the local address information associated to the object.
	</p>

	<p class="return">
	The method returns a string with local IP
	address and a number with the port. In case of error, the method
	returns <b><tt>nil</tt></b>.
	</p>

	<p class="note">
	Note: UDP sockets are not bound to any address
	until the <a href="#setsockname"><tt>setsockname</tt></a> or the
	<a href="#sendto"><tt>sendto</tt></a> method is called for the
	first time (in which case it is bound to an ephemeral port and the
	wild-card address).
	</p>

	<!-- receive +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="receive">
	connected:<b>receive(</b>[size]<b>)</b><br>
	unconnected:<b>receive(</b>[size]<b>)</b>
	</p>

	<p class="description">
	Receives a datagram from the UDP object. If
	the UDP object is connected, only datagrams coming from the peer
	are accepted. Otherwise, the returned datagram can come from any
	host.
	</p>

	<p class="parameters">
	The optional <tt>size</tt> parameter
	specifies the maximum size of the datagram to be retrieved. If
	there are more than <tt>size</tt> bytes available in the datagram,
	the excess bytes are discarded. If there are less then
	<tt>size</tt> bytes available in the current datagram, the
	available bytes are returned. If <tt>size</tt> is omitted, the
	maximum datagram size is used (which is currently limited by the
	implementation to 8192 bytes).
	</p>

	<p class="return">
	In case of success, the method returns the
	received datagram. In case of timeout, the method returns
	<b><tt>nil</tt></b> followed by the string '<tt>timeout</tt>'.
	</p>

	<!-- receivefrom +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="receivefrom">
	unconnected:<b>receivefrom(</b>[size]<b>)</b>
	</p>

	<p class="description">
	Works exactly as the <a href="#receive"><tt>receive</tt></a>
	method, except it returns the IP
	address and port as extra return values (and is therefore slightly less
	efficient).
	</p>

	<!-- send ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="send">
	connected:<b>send(</b>datagram<b>)</b>
	</p>

	<p class="description">
	Sends a datagram to the UDP peer of a connected object.
	</p>

	<p class="parameters">
	<tt>Datagram</tt> is a string with the datagram contents.
	The maximum datagram size for UDP is 64K minus IP layer overhead.
	However datagrams larger than the link layer packet size will be
	fragmented, which may deteriorate performance and/or reliability.
	</p>

	<p class="return">
	If successful, the method returns 1. In case of
	error, the method returns <b><tt>nil</tt></b> followed by an error message.
	</p>

	<p class="note">
	Note: In UDP, the <tt>send</tt> method never blocks
	and the only way it can fail is if the underlying transport layer
	refuses to send a message to the specified address (i.e. no
	interface accepts the address).
	</p>

	<!-- sendto ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="sendto">
	unconnected:<b>sendto(</b>datagram, ip, port<b>)</b>
	</p>

	<p class="description">
	Sends a datagram to the specified IP address and port number.
	</p>

	<p class="parameters">
	<tt>Datagram</tt> is a string with the
	datagram contents.
	The maximum datagram size for UDP is 64K minus IP layer overhead.
	However datagrams larger than the link layer packet size will be
	fragmented, which may deteriorate performance and/or reliability.
	<tt>Ip</tt> is the IP address of the recipient.
	Host names are <em>not</em> allowed for performance reasons.

	<tt>Port</tt> is the port number at the recipient.
	</p>

	<p class="return">
	If successful, the method returns 1. In case of
	error, the method returns <b><tt>nil</tt></b> followed by an error message.
	</p>

	<p class="note">
	Note: In UDP, the <tt>send</tt> method never blocks
	and the only way it can fail is if the underlying transport layer
	refuses to send a message to the specified address (i.e. no
	interface accepts the address).
	</p>

	<!-- setpeername +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="setpeername">
	connected:<b>setpeername(</b>'*'<b>)</b><br>
	unconnected:<b>setpeername(</b>address, port<b>)</b>
	</p>

	<p class="description">
	Changes the peer of a UDP object. This
	method turns an unconnected UDP object into a connected UDP
	object or vice versa.
	</p>

	<p class="description">
	For connected objects, outgoing datagrams
	will be sent to the specified peer, and datagrams received from
	other peers will be discarded by the OS. Connected UDP objects must
	use the <a href="#send"><tt>send</tt></a> and
	<a href="#receive"><tt>receive</tt></a> methods instead of
	<a href="#sendto"><tt>sendto</tt></a> and
	<a href="#receivefrom"><tt>receivefrom</tt></a>.
	</p>

	<p class="parameters">
	<tt>Address</tt> can be an IP address or a
	host name. <tt>Port</tt> is the port number. If <tt>address</tt> is
	'<tt>*</tt>' and the object is connected, the peer association is
	removed and the object becomes an unconnected object again. In that
	case, the <tt>port</tt> argument is ignored.
	</p>

	<p class="return">
	In case of error the method returns
	<b><tt>nil</tt></b> followed by an error message. In case of success, the
	method returns 1.
	</p>

	<p class="note">
	Note: Since the address of the peer does not have
	to be passed to and from the OS, the use of connected UDP objects
	is recommended when the same peer is used for several transmissions
	and can result in up to 30% performance gains.
	</p>

	<!-- setsockname +++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="setsockname">
	unconnected:<b>setsockname(</b>address, port<b>)</b>
	</p>

	<p class="description">
	Binds the UDP object to a local address.
	</p>

	<p class="parameters">
	<tt>Address</tt> can be an IP address or a
	host name. If <tt>address</tt> is '<tt>*</tt>' the system binds to
	all local interfaces using the constant <tt>INADDR_ANY</tt>. If
	<tt>port</tt> is 0, the system chooses an ephemeral port.
	</p>

	<p class="return">
	If successful, the method returns 1. In case of
	error, the method returns <b><tt>nil</tt></b> followed by an error
	message.
	</p>

	<p class="note">
	Note: This method can only be called before any
	datagram is sent through the UDP object, and only once. Otherwise,
	the system automatically binds the object to all local interfaces
	and chooses an ephemeral port as soon as the first datagram is
	sent. After the local address is set, either automatically by the
	system or explicitly by <tt>setsockname</tt>, it cannot be
	changed.
	</p>

	<!-- setoption +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="setoption">
	connected:<b>setoption(</b>option [, value]<b>)</b><br>
	unconnected:<b>setoption(</b>option [, value]<b>)</b>
	</p>

	<p class="description">
	Sets options for the UDP object. Options are
	only needed by low-level or time-critical applications. You should
	only modify an option if you are sure you need it.</p>
	<p class="parameters"><tt>Option</tt> is a string with the option
	name, and <tt>value</tt> depends on the option being set:
	</p>

	<ul>
	<li>'<tt>dontroute</tt>': Setting this option to <tt>true</tt>
	indicates that outgoing messages should bypass the standard routing
	facilities;</li>
	<li>'<tt>broadcast</tt>': Setting this option to <tt>true</tt>
	requests permission to send broadcast datagrams on the
	socket.</li>
	</ul>

	<p class="return">
	The method returns 1 in case of success, or
	<b><tt>nil</tt></b> followed by an error message otherwise.
	</p>

	<p class="note">
	Note: The descriptions above come from the man
	pages.
	</p>

	<!-- settimeout +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->

	<p class="name" id="settimeout">
	connected:<b>settimeout(</b>value<b>)</b><br>
	unconnected:<b>settimeout(</b>value<b>)</b>
	</p>

	<p class="description">
	Changes the timeout values for the object. By default, the
	<a href="#receive"><tt>receive</tt></a> and
	<a href="#receivefrom"><tt>receivefrom</tt></a>
	operations are blocking. That is, any call to the methods will block
	indefinitely, until data arrives. The <tt>settimeout</tt> function defines
	a limit on the amount of time the functions can block. When a timeout is
	set and the specified amount of time has elapsed, the affected methods
	give up and fail with an error code.
	</p>

	<p class="parameters">
	The amount of time to wait is specified as
	the <tt>value</tt> parameter, in seconds. The <b><tt>nil</tt></b> timeout
	<tt>value</tt> allows operations to block indefinitely. Negative
	timeout values have the same effect.
	</p>

	<p class="note">
	Note: In UDP, the <a href="#send"><tt>send</tt></a>
	and <a href="#sentdo"><tt>sendto</tt></a> methods never block (the
	datagram is just passed to the OS and the call returns
	immediately). Therefore, the <tt>settimeout</tt> method has no
	effect on them.
	</p>

	<p class="note">
	Note: The old <tt>timeout</tt> method is
	deprecated. The name has been changed for sake of uniformity, since
	all other method names already contained verbs making their
	imperative nature obvious.
	</p>

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