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diff --git a/doc/html/qsocketnotifier.html b/doc/html/qsocketnotifier.html new file mode 100644 index 0000000..48da714 --- /dev/null +++ b/doc/html/qsocketnotifier.html @@ -0,0 +1,183 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/kernel/qsocketnotifier.cpp:49 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QSocketNotifier Class</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QSocketNotifier Class Reference</h1> + +<p>The QSocketNotifier class provides support for socket callbacks. +<a href="#details">More...</a> +<p><tt>#include <<a href="qsocketnotifier-h.html">qsocketnotifier.h</a>></tt> +<p>Inherits <a href="qobject.html">QObject</a>. +<p><a href="qsocketnotifier-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn>enum <a href="#Type-enum"><b>Type</b></a> { Read, Write, Exception }</li> +<li class=fn><a href="#QSocketNotifier"><b>QSocketNotifier</b></a> ( int socket, Type type, QObject * parent = 0, const char * name = 0 )</li> +<li class=fn><a href="#~QSocketNotifier"><b>~QSocketNotifier</b></a> ()</li> +<li class=fn>int <a href="#socket"><b>socket</b></a> () const</li> +<li class=fn>Type <a href="#type"><b>type</b></a> () const</li> +<li class=fn>bool <a href="#isEnabled"><b>isEnabled</b></a> () const</li> +<li class=fn>virtual void <a href="#setEnabled"><b>setEnabled</b></a> ( bool enable )</li> +</ul> +<h2>Signals</h2> +<ul> +<li class=fn>void <a href="#activated"><b>activated</b></a> ( int socket )</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QSocketNotifier class provides support for socket callbacks. +<p> +<p> This class makes it possible to write asynchronous socket-based +code in Qt. Using synchronous socket operations blocks the +program, which is clearly not acceptable for an event-driven GUI +program. +<p> Once you have opened a non-blocking socket (whether for TCP, UDP, +a UNIX-domain socket, or any other protocol family your operating +system supports), you can create a socket notifier to monitor the +socket. Then you connect the <a href="#activated">activated</a>() signal to the slot you +want to be called when a socket event occurs. +<p> Note for Windows users: the socket passed to QSocketNotifier will +become non-blocking, even if it was created as a blocking socket. +<p> There are three types of socket notifiers (read, write and +exception); you must specify one of these in the constructor. +<p> The type specifies when the activated() signal is to be emitted: +<ol type=1> +<li> QSocketNotifier::Read - There is data to be read (socket read event). +<li> QSocketNotifier::Write - Data can be written (socket write event). +<li> QSocketNofifier::Exception - An exception has occurred (socket +exception event). We recommend against using this. +</ol> +<p> For example, if you need to monitor both reads and writes for the +same socket you must create two socket notifiers. +<p> For read notifiers it makes little sense to connect the +activated() signal to more than one slot because the data can be +read from the socket only once. +<p> Also observe that if you do not read all the available data when +the read notifier fires, it fires again and again. +<p> For write notifiers, immediately disable the notifier after the +<a href="#activated">activated</a>() signal has been received and you have sent the data to +be written on the socket. When you have more data to be written, +enable it again to get a new activated() signal. The exception is +if the socket data writing operation (send() or equivalent) fails +with a "would block" error, which means that some buffer is full +and you must wait before sending more data. In that case you do +not need to disable and re-enable the write notifier; it will fire +again as soon as the system allows more data to be sent. +<p> The behavior of a write notifier that is left in enabled state +after having emitting the first activated() signal (and no "would +block" error has occurred) is undefined. Depending on the +operating system, it may fire on every pass of the event loop or +not at all. +<p> If you need a time-out for your sockets you can use either <a href="qobject.html#startTimer">timer events</a> or the <a href="qtimer.html">QTimer</a> class. +<p> Socket action is detected in the <a href="qapplication.html#exec">main + event loop</a> of Qt. The X11 version of Qt has a single UNIX +select() call that incorporates all socket notifiers and the X +socket. +<p> Note that on XFree86 for OS/2, select() works only in the thread +in which main() is running; you should therefore use that thread +for GUI operations. +<p> <p>See also <a href="qsocket.html">QSocket</a>, <a href="qserversocket.html">QServerSocket</a>, <a href="qsocketdevice.html">QSocketDevice</a>, <a href="qfile.html#handle">QFile::handle</a>(), and <a href="io.html">Input/Output and Networking</a>. + +<hr><h2>Member Type Documentation</h2> +<h3 class=fn><a name="Type-enum"></a>QSocketNotifier::Type</h3> + +<ul> +<li><tt>QSocketNotifier::Read</tt> +<li><tt>QSocketNotifier::Write</tt> +<li><tt>QSocketNotifier::Exception</tt> +</ul> +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QSocketNotifier"></a>QSocketNotifier::QSocketNotifier ( int socket, <a href="qsocketnotifier.html#Type-enum">Type</a> type, <a href="qobject.html">QObject</a> * parent = 0, const char * name = 0 ) +</h3> +Constructs a socket notifier called <em>name</em>, with the parent, <em>parent</em>. It watches <em>socket</em> for <em>type</em> events, and enables it. +<p> It is generally advisable to explicitly enable or disable the +socket notifier, especially for write notifiers. +<p> <p>See also <a href="#setEnabled">setEnabled</a>() and <a href="#isEnabled">isEnabled</a>(). + +<h3 class=fn><a name="~QSocketNotifier"></a>QSocketNotifier::~QSocketNotifier () +</h3> +Destroys the socket notifier. + +<h3 class=fn>void <a name="activated"></a>QSocketNotifier::activated ( int socket )<tt> [signal]</tt> +</h3> + +<p> This signal is emitted under certain conditions specified by the +notifier <a href="#type">type</a>(): +<ol type=1> +<li> QSocketNotifier::Read - There is data to be read (socket read event). +<li> QSocketNotifier::Write - Data can be written (socket write event). +<li> QSocketNofifier::Exception - An exception has occurred (socket +exception event). +</ol> +<p> The <em>socket</em> argument is the <a href="#socket">socket</a> identifier. +<p> <p>See also <a href="#type">type</a>() and <a href="#socket">socket</a>(). + +<h3 class=fn>bool <a name="isEnabled"></a>QSocketNotifier::isEnabled () const +</h3> + +<p> Returns TRUE if the notifier is enabled; otherwise returns FALSE. +<p> <p>See also <a href="#setEnabled">setEnabled</a>(). + +<h3 class=fn>void <a name="setEnabled"></a>QSocketNotifier::setEnabled ( bool enable )<tt> [virtual]</tt> +</h3> +Enables the notifier if <em>enable</em> is TRUE or disables it if <em>enable</em> is FALSE. +<p> The notifier is enabled by default. +<p> If the notifier is enabled, it emits the <a href="#activated">activated</a>() signal +whenever a socket event corresponding to its <a href="#type">type</a> occurs. If it is disabled, it ignores socket events +(the same effect as not creating the socket notifier). +<p> Write notifiers should normally be disabled immediately after the +activated() signal has been emitted; see discussion of write +notifiers in the <a href="#details">class description</a> above. +<p> <p>See also <a href="#isEnabled">isEnabled</a>() and <a href="#activated">activated</a>(). + +<h3 class=fn>int <a name="socket"></a>QSocketNotifier::socket () const +</h3> + +<p> Returns the socket identifier specified to the constructor. +<p> <p>See also <a href="#type">type</a>(). + +<h3 class=fn><a href="qsocketnotifier.html#Type-enum">Type</a> <a name="type"></a>QSocketNotifier::type () const +</h3> + +<p> Returns the socket event type specified to the constructor: <a href="#Type-enum">QSocketNotifier::Read</a>, <a href="#Type-enum">QSocketNotifier::Write</a>, or <a href="#Type-enum">QSocketNotifier::Exception</a>. +<p> <p>See also <a href="#socket">socket</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. 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