source: trunk/src/corelib/kernel/qsocketnotifier.cpp@ 991

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#include "qsocketnotifier.h"

#include "qplatformdefs.h"

#include "qabstracteventdispatcher.h"
#include "qcoreapplication.h"

#include "qobject_p.h"
#include <private/qthread_p.h>

QT_BEGIN_NAMESPACE

/*!
    \class QSocketNotifier
    \brief The QSocketNotifier class provides support for monitoring
    activity on a file descriptor.

    \ingroup network
    \ingroup io

    The QSocketNotifier makes it possible to integrate Qt's event
    loop with other event loops based on file descriptors. For
    example, the \l{CORBA Framework} uses it to process CORBA
    events.  File descriptor action is detected in Qt's main event
    loop (QCoreApplication::exec()).

    \target write notifiers

    Once you have opened a device using a low-level (usually
    platform-specific) API, you can create a socket notifier to
    monitor the file descriptor. The socket notifier is enabled by
    default, i.e. it emits the activated() signal whenever a socket
    event corresponding to its type occurs. Connect the activated()
    signal to the slot you want to be called when an event
    corresponding to your socket notifier's type occurs.

    There are three types of socket notifiers: read, write, and
    exception. The type is described by the \l Type enum, and must be
    specified when constructing the socket notifier. After
    construction it can be determined using the type() function. Note
    that if you need to monitor both reads and writes for the same
    file descriptor, you must create two socket notifiers. Note also
    that it is not possible to install two socket notifiers of the
    same type (\l Read, \l Write, \l Exception) on the same socket.

    The setEnabled() function allows you to disable as well as enable
    the socket notifier. It is generally advisable to explicitly
    enable or disable the socket notifier, especially for write
    notifiers. A disabled notifier ignores socket events (the same
    effect as not creating the socket notifier). Use the isEnabled()
    function to determine the notifier's current status.