The QTcpSocket class provides a TCP socket. More...

#include <qtcpsocket.h>

Inheritance diagram for QTcpSocket:

Collaboration diagram for QTcpSocket:

Public Member Functions
	QTcpSocket (QObject *parent=nullptr)
	Creates a QTcpSocket object in state `UnconnectedState`.
virtual	~QTcpSocket ()
	Destroys the socket, closing the connection if necessary.
Public Member Functions inherited from QAbstractSocket
	QAbstractSocket (SocketType socketType, QObject *parent)
	Creates a new abstract socket of type socketType.
virtual	~QAbstractSocket ()
	Destroys the socket.
virtual void	resume ()
PauseModes	pauseMode () const
void	setPauseMode (PauseModes pauseMode)
virtual bool	bind (const QHostAddress &address, quint16 port=0, BindMode mode=DefaultForPlatform)
bool	bind (QHostAddress::SpecialAddress addr, quint16 port=0, BindMode mode=DefaultForPlatform)
bool	bind (quint16 port=0, BindMode mode=DefaultForPlatform)
virtual void	connectToHost (const QString &hostName, quint16 port, OpenMode mode=ReadWrite, NetworkLayerProtocol protocol=AnyIPProtocol)
	Attempts to make a connection to hostName on the given port.
void	connectToHost (const QHostAddress &address, quint16 port, OpenMode mode=ReadWrite)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Attempts to make a connection to address on port port.
virtual void	disconnectFromHost ()
	Attempts to close the socket.
bool	isValid () const
	Returns `true` if the socket is valid and ready for use; otherwise returns `false`.
qint64	bytesAvailable () const override
	Returns the number of incoming bytes that are waiting to be read.
qint64	bytesToWrite () const override
	Returns the number of bytes that are waiting to be written.
quint16	localPort () const
	Returns the host port number (in native byte order) of the local socket if available; otherwise returns 0.
QHostAddress	localAddress () const
	Returns the host address of the local socket if available; otherwise returns QHostAddress::Null.
quint16	peerPort () const
	Returns the port of the connected peer if the socket is in ConnectedState; otherwise returns 0.
QHostAddress	peerAddress () const
	Returns the address of the connected peer if the socket is in ConnectedState; otherwise returns QHostAddress::Null.
QString	peerName () const
	Returns the name of the peer as specified by connectToHost(), or an empty QString if connectToHost() has not been called.
qint64	readBufferSize () const
	Returns the size of the internal read buffer.
virtual void	setReadBufferSize (qint64 size)
	Sets the size of QAbstractSocket's internal read buffer to be size bytes.
void	abort ()
	Aborts the current connection and resets the socket.
virtual qintptr	socketDescriptor () const
	Returns the native socket descriptor of the QAbstractSocket object if this is available; otherwise returns -1.
virtual bool	setSocketDescriptor (qintptr socketDescriptor, SocketState state=ConnectedState, OpenMode openMode=ReadWrite)
	Initializes QAbstractSocket with the native socket descriptor socketDescriptor.
virtual void	setSocketOption (QAbstractSocket::SocketOption option, const QVariant &value)
virtual QVariant	socketOption (QAbstractSocket::SocketOption option)
SocketType	socketType () const
	Returns the socket type (TCP, UDP, or other).
SocketState	state () const
	Returns the state of the socket.
SocketError	error () const
	Returns the type of error that last occurred.
void	close () override
	Closes the I/O device for the socket and calls disconnectFromHost() to close the socket's connection.
bool	isSequential () const override
	\reimp
bool	flush ()
	This function writes as much as possible from the internal write buffer to the underlying network socket, without blocking.
virtual bool	waitForConnected (int msecs=30000)
	Waits until the socket is connected, up to msecs milliseconds.
bool	waitForReadyRead (int msecs=30000) override
	This function blocks until new data is available for reading and the \l{QIODevice::}{readyRead()} signal has been emitted.
bool	waitForBytesWritten (int msecs=30000) override
	\reimp
virtual bool	waitForDisconnected (int msecs=30000)
	Waits until the socket has disconnected, up to msecs milliseconds.
void	setProxy (const QNetworkProxy &networkProxy)
QNetworkProxy	proxy () const
QString	protocolTag () const
void	setProtocolTag (const QString &tag)

Protected Member Functions
	QTcpSocket (QTcpSocketPrivate &dd, QObject *parent=nullptr)
	QTcpSocket (QAbstractSocket::SocketType socketType, QTcpSocketPrivate &dd, QObject *parent=nullptr)
Protected Member Functions inherited from QAbstractSocket
qint64	readData (char *data, qint64 maxlen) override
	\reimp
qint64	readLineData (char *data, qint64 maxlen) override
	\reimp
qint64	skipData (qint64 maxSize) override
	\reimp
qint64	writeData (const char *data, qint64 len) override
	\reimp
void	setSocketState (SocketState state)
	Sets the state of the socket to state.
void	setSocketError (SocketError socketError)
	Sets the type of error that last occurred to socketError.
void	setLocalPort (quint16 port)
void	setLocalAddress (const QHostAddress &address)
void	setPeerPort (quint16 port)
void	setPeerAddress (const QHostAddress &address)
void	setPeerName (const QString &name)
	QAbstractSocket (SocketType socketType, QAbstractSocketPrivate &dd, QObject *parent=nullptr)

Additional Inherited Members
Public Types inherited from QAbstractSocket
enum	SocketType { TcpSocket , UdpSocket , SctpSocket , UnknownSocketType = -1 }
	This enum describes the transport layer protocol. More...
enum	SocketError { ConnectionRefusedError , RemoteHostClosedError , HostNotFoundError , SocketAccessError , SocketResourceError , SocketTimeoutError , DatagramTooLargeError , NetworkError , AddressInUseError , SocketAddressNotAvailableError , UnsupportedSocketOperationError , UnfinishedSocketOperationError , ProxyAuthenticationRequiredError , SslHandshakeFailedError , ProxyConnectionRefusedError , ProxyConnectionClosedError , ProxyConnectionTimeoutError , ProxyNotFoundError , ProxyProtocolError , OperationError , SslInternalError , SslInvalidUserDataError , TemporaryError , UnknownSocketError = -1 }
	This enum describes the socket errors that can occur. More...
enum	SocketState { UnconnectedState , HostLookupState , ConnectingState , ConnectedState , BoundState , ListeningState , ClosingState }
	This enum describes the different states in which a socket can be. More...
enum	SocketOption { LowDelayOption , KeepAliveOption , MulticastTtlOption , MulticastLoopbackOption , TypeOfServiceOption , SendBufferSizeSocketOption , ReceiveBufferSizeSocketOption , PathMtuSocketOption }
enum	BindFlag { DefaultForPlatform = 0x0 , ShareAddress = 0x1 , DontShareAddress = 0x2 , ReuseAddressHint = 0x4 }
enum	PauseMode { PauseNever = 0x0 , PauseOnSslErrors = 0x1 }
Public Types inherited from QtPrivate::QAbstractSocketConstants
using	NetworkLayerProtocol = QHostAddress::NetworkLayerProtocol
Signals inherited from QAbstractSocket
void	hostFound ()
	This signal is emitted after connectToHost() has been called and the host lookup has succeeded.
void	connected ()
	This signal is emitted after connectToHost() has been called and a connection has been successfully established.
void	disconnected ()
	This signal is emitted when the socket has been disconnected.
void	stateChanged (QAbstractSocket::SocketState)
	This signal is emitted whenever QAbstractSocket's state changes.
void	errorOccurred (QAbstractSocket::SocketError)
void	proxyAuthenticationRequired (const QNetworkProxy &proxy, QAuthenticator *authenticator)
Static Public Attributes inherited from QtPrivate::QAbstractSocketConstants
static constexpr auto	IPv4Protocol = QHostAddress::IPv4Protocol
static constexpr auto	IPv6Protocol = QHostAddress::IPv6Protocol
static constexpr auto	AnyIPProtocol = QHostAddress::AnyIPProtocol
static constexpr auto	UnknownNetworkLayerProtocol = QHostAddress::UnknownNetworkLayerProtocol

Detailed Description

The QTcpSocket class provides a TCP socket.

\reentrant

\inmodule QtNetwork

TCP (Transmission Control Protocol) is a reliable, stream-oriented, connection-oriented transport protocol. It is especially well suited for continuous transmission of data.

QTcpSocket is a convenience subclass of QAbstractSocket that allows you to establish a TCP connection and transfer streams of data. See the QAbstractSocket documentation for details.

Note: TCP sockets cannot be opened in \l QIODeviceBase::Unbuffered mode.

See also: QTcpServer, QUdpSocket, QNetworkAccessManager, {Fortune Server}, {Fortune Client}, {Threaded Fortune Server}, {Blocking Fortune Client}, {Torrent Example}

Definition at line 18 of file qtcpsocket.h.

Constructor & Destructor Documentation

◆ QTcpSocket() [1/3]

QT_BEGIN_NAMESPACE QTcpSocket::QTcpSocket ( QObject * parent = nullptr )

explicit

Creates a QTcpSocket object in state UnconnectedState.

parent is passed on to the QObject constructor.

See also: socketType()

Definition at line 46 of file qtcpsocket.cpp.

◆ ~QTcpSocket()

QTcpSocket::~QTcpSocket ( )

virtual

Destroys the socket, closing the connection if necessary.

See also: close()

Definition at line 61 of file qtcpsocket.cpp.

◆ QTcpSocket() [2/3]

QTcpSocket::QTcpSocket	(	QTcpSocketPrivate &	dd,
		QObject *	parent = nullptr )

protected

Definition at line 71 of file qtcpsocket.cpp.

◆ QTcpSocket() [3/3]

QTcpSocket::QTcpSocket	(	QAbstractSocket::SocketType	socketType,
		QTcpSocketPrivate &	dd,
		QObject *	parent = nullptr )

protected

Definition at line 80 of file qtcpsocket.cpp.

The documentation for this class was generated from the following files:

qtbase/src/network/socket/qtcpsocket.h (7a308dccb5d425cfbbdbdcc8ce1545d0c66a2c76)
qtbase/src/network/socket/qtcpsocket.cpp (7a308dccb5d425cfbbdbdcc8ce1545d0c66a2c76)

Public Member Functions