The QLocalSocket class provides a local socket. More...

#include <qlocalsocket.h>

Inheritance diagram for QLocalSocket:

Collaboration diagram for QLocalSocket:

Public Types
enum	LocalSocketError { ConnectionRefusedError = QAbstractSocket::ConnectionRefusedError , PeerClosedError = QAbstractSocket::RemoteHostClosedError , ServerNotFoundError = QAbstractSocket::HostNotFoundError , SocketAccessError = QAbstractSocket::SocketAccessError , SocketResourceError = QAbstractSocket::SocketResourceError , SocketTimeoutError = QAbstractSocket::SocketTimeoutError , DatagramTooLargeError = QAbstractSocket::DatagramTooLargeError , ConnectionError = QAbstractSocket::NetworkError , UnsupportedSocketOperationError = QAbstractSocket::UnsupportedSocketOperationError , UnknownSocketError = QAbstractSocket::UnknownSocketError , OperationError = QAbstractSocket::OperationError }
	The LocalServerError enumeration represents the errors that can occur. More...

enum	LocalSocketState { UnconnectedState = QAbstractSocket::UnconnectedState , ConnectingState = QAbstractSocket::ConnectingState , ConnectedState = QAbstractSocket::ConnectedState , ClosingState = QAbstractSocket::ClosingState }
	This enum describes the different states in which a socket can be. More...

enum	SocketOption { NoOptions = 0x00 , AbstractNamespaceOption = 0x01 }

Public Types inherited from QIODeviceBase
enum	OpenModeFlag { NotOpen = 0x0000 , ReadOnly = 0x0001 , WriteOnly = 0x0002 , ReadWrite = ReadOnly \| WriteOnly , Append = 0x0004 , Truncate = 0x0008 , Text = 0x0010 , Unbuffered = 0x0020 , NewOnly = 0x0040 , ExistingOnly = 0x0080 }
	This enum is used with QIODevice::open() to describe the mode in which a device is opened. More...

Signals
void	connected ()
	This signal is emitted after connectToServer() has been called and a connection has been successfully established.

void	disconnected ()
	This signal is emitted when the socket has been disconnected.

void	errorOccurred (QLocalSocket::LocalSocketError socketError)

void	stateChanged (QLocalSocket::LocalSocketState socketState)
	This signal is emitted whenever QLocalSocket's state changes.

Signals inherited from QIODevice
void	readyRead ()
	This signal is emitted once every time new data is available for reading from the device's current read channel.

void	channelReadyRead (int channel)

void	bytesWritten (qint64 bytes)
	This signal is emitted every time a payload of data has been written to the device's current write channel.

void	channelBytesWritten (int channel, qint64 bytes)

void	aboutToClose ()
	This signal is emitted when the device is about to close.

void	readChannelFinished ()

Signals inherited from QObject
void	destroyed (QObject *=nullptr)
	This signal is emitted immediately before the object obj is destroyed, after any instances of QPointer have been notified, and cannot be blocked.

void	objectNameChanged (const QString &objectName, QPrivateSignal)
	This signal is emitted after the object's name has been changed.

Public Member Functions
	QLocalSocket (QObject *parent=nullptr)
	Creates a new local socket.

	~QLocalSocket ()
	Destroys the socket, closing the connection if necessary.

void	connectToServer (OpenMode openMode=ReadWrite)

void	connectToServer (const QString &name, OpenMode openMode=ReadWrite)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Set the server name and attempts to make a connection to it.

void	disconnectFromServer ()
	Attempts to close the socket.

void	setServerName (const QString &name)

QString	serverName () const
	Returns the name of the peer as specified by setServerName(), or an empty QString if setServerName() has not been called or connectToServer() failed.

QString	fullServerName () const
	Returns the server path that the socket is connected to.

void	abort ()
	Aborts the current connection and resets the socket.

virtual bool	isSequential () const override
	\reimp

virtual qint64	bytesAvailable () const override
	\reimp

virtual qint64	bytesToWrite () const override
	\reimp

virtual bool	canReadLine () const override
	\reimp

virtual bool	open (OpenMode openMode=ReadWrite) override
	Equivalent to connectToServer(OpenMode mode).

virtual void	close () override
	Closes the I/O device for the socket and calls disconnectFromServer() to close the socket's connection.

LocalSocketError	error () const
	Returns the type of error that last occurred.

bool	flush ()
	This function writes as much as possible from the internal write buffer to the socket, without blocking.

bool	isValid () const
	Returns `true` if the socket is valid and ready for use; otherwise returns `false`.

qint64	readBufferSize () const
	Returns the size of the internal read buffer.

void	setReadBufferSize (qint64 size)
	Sets the size of QLocalSocket's internal read buffer to be size bytes.

bool	setSocketDescriptor (qintptr socketDescriptor, LocalSocketState socketState=ConnectedState, OpenMode openMode=ReadWrite)
	Initializes QLocalSocket with the native socket descriptor socketDescriptor.

qintptr	socketDescriptor () const
	Returns the native socket descriptor of the QLocalSocket object if this is available; otherwise returns -1.

void	setSocketOptions (SocketOptions option)

SocketOptions	socketOptions () const

QBindable< SocketOptions >	bindableSocketOptions ()

LocalSocketState	state () const
	Returns the state of the socket.

bool	waitForBytesWritten (int msecs=30000) override
	\reimp

bool	waitForConnected (int msecs=30000)
	Waits until the socket is connected, up to msecs milliseconds.

bool	waitForDisconnected (int msecs=30000)
	Waits until the socket has disconnected, up to msecs milliseconds.

bool	waitForReadyRead (int msecs=30000) override
	This function blocks until data is available for reading and the \l{QIODevice::}{readyRead()} signal has been emitted.

Public Member Functions inherited from QIODevice
	QIODevice ()
	Constructs a QIODevice object.

	QIODevice (QObject *parent)
	Constructs a QIODevice object with the given parent.

virtual	~QIODevice ()
	The destructor is virtual, and QIODevice is an abstract base class.

QIODeviceBase::OpenMode	openMode () const
	Returns the mode in which the device has been opened; i.e.

void	setTextModeEnabled (bool enabled)
	If enabled is true, this function sets the \l Text flag on the device; otherwise the \l Text flag is removed.

bool	isTextModeEnabled () const
	Returns `true` if the \l Text flag is enabled; otherwise returns `false`.

bool	isOpen () const
	Returns `true` if the device is open; otherwise returns `false`.

bool	isReadable () const
	Returns `true` if data can be read from the device; otherwise returns false.

bool	isWritable () const
	Returns `true` if data can be written to the device; otherwise returns false.

virtual bool	isSequential () const
	Returns `true` if this device is sequential; otherwise returns false.

int	readChannelCount () const

int	writeChannelCount () const

int	currentReadChannel () const

void	setCurrentReadChannel (int channel)

int	currentWriteChannel () const

void	setCurrentWriteChannel (int channel)

virtual bool	open (QIODeviceBase::OpenMode mode)
	Opens the device and sets its OpenMode to mode.

virtual void	close ()
	First emits aboutToClose(), then closes the device and sets its OpenMode to NotOpen.

virtual qint64	pos () const
	For random-access devices, this function returns the position that data is written to or read from.

virtual qint64	size () const
	For open random-access devices, this function returns the size of the device.

virtual bool	seek (qint64 pos)
	For random-access devices, this function sets the current position to pos, returning true on success, or false if an error occurred.

virtual bool	atEnd () const
	Returns `true` if the current read and write position is at the end of the device (i.e.

virtual bool	reset ()
	Seeks to the start of input for random-access devices.

virtual qint64	bytesAvailable () const
	Returns the number of bytes that are available for reading.

virtual qint64	bytesToWrite () const
	For buffered devices, this function returns the number of bytes waiting to be written.

qint64	read (char *data, qint64 maxlen)
	Reads at most maxSize bytes from the device into data, and returns the number of bytes read.

QByteArray	read (qint64 maxlen)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Reads at most maxSize bytes from the device, and returns the data read as a QByteArray.

QByteArray	readAll ()
	Reads all remaining data from the device, and returns it as a byte array.

qint64	readLine (char *data, qint64 maxlen)
	This function reads a line of ASCII characters from the device, up to a maximum of maxSize - 1 bytes, stores the characters in data, and returns the number of bytes read.

QByteArray	readLine (qint64 maxlen=0)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Reads a line from the device, but no more than maxSize characters, and returns the result as a byte array.

virtual bool	canReadLine () const
	Returns `true` if a complete line of data can be read from the device; otherwise returns `false`.

void	startTransaction ()

void	commitTransaction ()

void	rollbackTransaction ()

bool	isTransactionStarted () const

qint64	write (const char *data, qint64 len)
	Writes at most maxSize bytes of data from data to the device.

qint64	write (const char *data)

qint64	write (const QByteArray &data)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Writes the content of data to the device.

qint64	peek (char *data, qint64 maxlen)

QByteArray	peek (qint64 maxlen)

qint64	skip (qint64 maxSize)

virtual bool	waitForReadyRead (int msecs)
	Blocks until new data is available for reading and the readyRead() signal has been emitted, or until msecs milliseconds have passed.

virtual bool	waitForBytesWritten (int msecs)
	For buffered devices, this function waits until a payload of buffered written data has been written to the device and the bytesWritten() signal has been emitted, or until msecs milliseconds have passed.

void	ungetChar (char c)
	Puts the character c back into the device, and decrements the current position unless the position is 0.

bool	putChar (char c)
	Writes the character c to the device.

bool	getChar (char *c)
	Reads one character from the device and stores it in c.

QString	errorString () const
	Returns a human-readable description of the last device error that occurred.

Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)
	Constructs an object with parent object parent.

virtual	~QObject ()
	Destroys the object, deleting all its child objects.

virtual bool	event (QEvent *event)
	This virtual function receives events to an object and should return true if the event e was recognized and processed.

virtual bool	eventFilter (QObject watched, QEvent event)
	Filters events if this object has been installed as an event filter for the watched object.

QString	objectName () const

Q_WEAK_OVERLOAD void	setObjectName (const QString &name)
	Sets the object's name to name.

void	setObjectName (QAnyStringView name)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

QBindable< QString >	bindableObjectName ()

bool	isWidgetType () const
	Returns `true` if the object is a widget; otherwise returns `false`.

bool	isWindowType () const
	Returns `true` if the object is a window; otherwise returns `false`.

bool	isQuickItemType () const
	Returns `true` if the object is a QQuickItem; otherwise returns `false`.

bool	signalsBlocked () const noexcept
	Returns `true` if signals are blocked; otherwise returns `false`.

bool	blockSignals (bool b) noexcept
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it).

QThread *	thread () const
	Returns the thread in which the object lives.

void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children.

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
	This is an overloaded function that will start a timer of type timerType and a timeout of interval milliseconds.

int	startTimer (std::chrono::milliseconds time, Qt::TimerType timerType=Qt::CoarseTimer)

void	killTimer (int id)
	Kills the timer with timer identifier, id.

template<typename T >
T	findChild (const QString &aName=QString(), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns the child of this object that can be cast into type T and that is called name, or \nullptr if there is no such object.

template<typename T >
QList< T >	findChildren (const QString &aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects.

template<typename T >
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

const QObjectList &	children () const
	Returns a list of child objects.

void	setParent (QObject *parent)
	Makes the object a child of parent.

void	installEventFilter (QObject *filterObj)
	Installs an event filter filterObj on this object.

void	removeEventFilter (QObject *obj)
	Removes an event filter object obj from this object.

QMetaObject::Connection	connect (const QObject sender, const char signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const

bool	disconnect (const char signal=nullptr, const QObject receiver=nullptr, const char *member=nullptr) const

bool	disconnect (const QObject receiver, const char member=nullptr) const

void	dumpObjectTree () const
	Dumps a tree of children to the debug output.

void	dumpObjectInfo () const
	Dumps information about signal connections, etc.

bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value.

bool	setProperty (const char *name, QVariant &&value)

QVariant	property (const char *name) const
	Returns the value of the object's name property.

QList< QByteArray >	dynamicPropertyNames () const

QBindingStorage *	bindingStorage ()

const QBindingStorage *	bindingStorage () const

QObject *	parent () const
	Returns a pointer to the parent object.

bool	inherits (const char *classname) const
	Returns `true` if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns `false`.

Protected Member Functions
virtual qint64	readData (char *, qint64) override
	\reimp

qint64	readLineData (char *data, qint64 maxSize) override
	\reimp

qint64	skipData (qint64 maxSize) override
	\reimp

virtual qint64	writeData (const char *, qint64) override
	\reimp

Protected Member Functions inherited from QIODevice
	QIODevice (QIODevicePrivate &dd, QObject *parent=nullptr)

virtual qint64	readData (char *data, qint64 maxlen)=0
	Reads up to maxSize bytes from the device into data, and returns the number of bytes read or -1 if an error occurred.

virtual qint64	readLineData (char *data, qint64 maxlen)
	Reads up to maxSize characters into data and returns the number of characters read.

virtual qint64	skipData (qint64 maxSize)

virtual qint64	writeData (const char *data, qint64 len)=0
	Writes up to maxSize bytes from data to the device.

void	setOpenMode (QIODeviceBase::OpenMode openMode)
	Sets the OpenMode of the device to openMode.

void	setErrorString (const QString &errorString)
	Sets the human readable description of the last device error that occurred to str.

Protected Member Functions inherited from QObject
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns \nullptr.

int	senderSignalIndex () const

int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal.

bool	isSignalConnected (const QMetaMethod &signal) const

virtual void	timerEvent (QTimerEvent *event)
	This event handler can be reimplemented in a subclass to receive timer events for the object.

virtual void	childEvent (QChildEvent *event)
	This event handler can be reimplemented in a subclass to receive child events.

virtual void	customEvent (QEvent *event)
	This event handler can be reimplemented in a subclass to receive custom events.

virtual void	connectNotify (const QMetaMethod &signal)

virtual void	disconnectNotify (const QMetaMethod &signal)

	QObject (QObjectPrivate &dd, QObject *parent=nullptr)

Protected Member Functions inherited from QIODeviceBase
	~QIODeviceBase ()=default

Properties
SocketOptions	socketOptions
	the socket options.

Properties inherited from QObject
QString	objectName
	the name of this object

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe

Static Public Member Functions inherited from QObject
static QMetaObject::Connection	connect (const QObject sender, const char signal, const QObject receiver, const char member, Qt::ConnectionType=Qt::AutoConnection)
	\threadsafe

static QMetaObject::Connection	connect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::ContextTypeForFunctor< Func2 >::ContextType context, Func2 &&slot, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 &&slot)

static bool	disconnect (const QObject sender, const char signal, const QObject receiver, const char member)
	\threadsafe

static bool	disconnect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &member)

static bool	disconnect (const QMetaObject::Connection &)
	Disconnect a connection.

template<typename Func1 , typename Func2 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::FunctionPointer< Func2 >::Object receiver, Func2 slot)

template<typename Func1 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const QObject receiver, void **zero)

Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr

Related Symbols inherited from QObject
template< class T > T	qobject_cast (const QObject *object)
	Returns the given object cast to type T if the object is of type T (or of a subclass); otherwise returns \nullptr.

template< typename T > T	qFindChildqFindChildren (const QObject *obj, const QString &name)()

template< typename T > QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()

	QObjectList
	\macro Q_CLASSINFO(Name, Value)

Detailed Description

The QLocalSocket class provides a local socket.

Since: 4.4 \inmodule QtNetwork

On Windows this is a named pipe and on Unix this is a local domain socket.

If an error occurs, error() returns the type of error, and errorString() can be called to get a human readable description of what happened.

Although QLocalSocket is designed for use with an event loop, it's possible to use it without one. In that case, you must use waitForConnected(), waitForReadyRead(), waitForBytesWritten(), and waitForDisconnected() which blocks until the operation is complete or the timeout expires.

See also: QLocalServer

Definition at line 21 of file qlocalsocket.h.

Member Enumeration Documentation

◆ LocalSocketError

enum QLocalSocket::LocalSocketError

The LocalServerError enumeration represents the errors that can occur.

The most recent error can be retrieved through a call to \l QLocalSocket::error().

\value ConnectionRefusedError The connection was refused by the peer (or timed out). \value PeerClosedError The remote socket closed the connection. Note that the client socket (i.e., this socket) will be closed after the remote close notification has been sent. \value ServerNotFoundError The local socket name was not found. \value SocketAccessError The socket operation failed because the application lacked the required privileges. \value SocketResourceError The local system ran out of resources (e.g., too many sockets). \value SocketTimeoutError The socket operation timed out. \value DatagramTooLargeError The datagram was larger than the operating system's limit (which can be as low as 8192 bytes). \value ConnectionError An error occurred with the connection. \value UnsupportedSocketOperationError The requested socket operation is not supported by the local operating system. \value OperationError An operation was attempted while the socket was in a state that did not permit it. \value UnknownSocketError An unidentified error occurred.

Enumerator
ConnectionRefusedError
PeerClosedError
ServerNotFoundError
SocketAccessError
SocketResourceError
SocketTimeoutError
DatagramTooLargeError
ConnectionError
UnsupportedSocketOperationError
UnknownSocketError
OperationError

Definition at line 29 of file qlocalsocket.h.

◆ LocalSocketState

enum QLocalSocket::LocalSocketState

This enum describes the different states in which a socket can be.

See also: QLocalSocket::state()

\value UnconnectedState The socket is not connected. \value ConnectingState The socket has started establishing a connection. \value ConnectedState A connection is established. \value ClosingState The socket is about to close (data may still be waiting to be written).

Enumerator
UnconnectedState
ConnectingState
ConnectedState
ClosingState

Definition at line 44 of file qlocalsocket.h.

◆ SocketOption

enum QLocalSocket::SocketOption

Since: 6.2 This enum describes the possible options that can be used to connect to a server. Currently, on Linux and Android it is used for specifying connection to a server listening to a socket bound to an abstract address.

\value NoOptions No options have been set. \value AbstractNamespaceOption The socket will try to connect to an abstract address. This flag is specific to Linux and Android. On other platforms is ignored.

See also: socketOptions

Enumerator
NoOptions
AbstractNamespaceOption

Definition at line 52 of file qlocalsocket.h.

Constructor & Destructor Documentation

◆ QLocalSocket()

QLocalSocket::QLocalSocket ( QObject * parent = nullptr )

Creates a new local socket.

The parent argument is passed to QObject's constructor.

Definition at line 358 of file qlocalsocket.cpp.

References d.

◆ ~QLocalSocket()

QLocalSocket::~QLocalSocket ( )

Destroys the socket, closing the connection if necessary.

Definition at line 370 of file qlocalsocket.cpp.

References abort(), and d.

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Member Function Documentation

◆ abort()

void QLocalSocket::abort ( )

Aborts the current connection and resets the socket.

Unlike disconnectFromServer(), this function immediately closes the socket, clearing any pending data in the write buffer.

See also: disconnectFromServer(), close()

Definition at line 288 of file qlocalsocket_tcp.cpp.

References close(), and d.

Referenced by ~QLocalSocket().

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◆ bindableSocketOptions()

QBindable< QLocalSocket::SocketOptions > QLocalSocket::bindableSocketOptions ( )

Definition at line 458 of file qlocalsocket.cpp.

References d.

◆ bytesAvailable()

qint64 QLocalSocket::bytesAvailable ( ) const

overridevirtual

\reimp

Reimplemented from QIODevice.

Definition at line 295 of file qlocalsocket_tcp.cpp.

References QIODevice::bytesAvailable(), and d.

Referenced by QBluetoothSocketPrivateBluezDBus::bytesAvailable().

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◆ bytesToWrite()

qint64 QLocalSocket::bytesToWrite ( ) const

overridevirtual

\reimp

Reimplemented from QIODevice.

Definition at line 301 of file qlocalsocket_tcp.cpp.

References d.

Referenced by QBluetoothSocketPrivateBluezDBus::bytesToWrite(), and QLocalClientConnection::disconnect().

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◆ canReadLine()

bool QLocalSocket::canReadLine ( ) const

overridevirtual

\reimp

Reimplemented from QIODevice.

Definition at line 307 of file qlocalsocket_tcp.cpp.

References QIODevice::canReadLine(), and d.

Referenced by QBluetoothSocketPrivateBluezDBus::canReadLine().

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◆ close()

void QLocalSocket::close ( )

overridevirtual

Closes the I/O device for the socket and calls disconnectFromServer() to close the socket's connection.

See QIODevice::close() for a description of the actions that occur when an I/O device is closed.

See also: abort()

Reimplemented from QIODevice.

Definition at line 313 of file qlocalsocket_tcp.cpp.

References QIODevice::close(), and d.

Referenced by abort(), and QBluetoothSocketPrivateBluezDBus::abort().

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◆ connected

void QLocalSocket::connected ( )

signal

This signal is emitted after connectToServer() has been called and a connection has been successfully established.

See also: connectToServer(), disconnected()

◆ connectToServer() [1/2]

void QLocalSocket::connectToServer	(	const QString &	name,
		OpenMode	openMode = `ReadWrite`
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Set the server name and attempts to make a connection to it.

The socket is opened in the given openMode and first enters ConnectingState. If a connection is established, QLocalSocket enters ConnectedState and emits connected().

After calling this function, the socket can emit errorOccurred() to signal that an error occurred.

See also: state(), serverName(), waitForConnected()

Definition at line 396 of file qlocalsocket.cpp.

References connectToServer(), QIODevice::openMode(), and setServerName().

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◆ connectToServer() [2/2]

void QLocalSocket::connectToServer ( OpenMode openMode = ReadWrite )

Since: 5.1

Attempts to make a connection to serverName(). setServerName() must be called before you open the connection. Alternatively you can use connectToServer(const QString &name, OpenMode openMode);

The socket is opened in the given openMode and first enters ConnectingState. If a connection is established, QLocalSocket enters ConnectedState and emits connected().

After calling this function, the socket can emit errorOccurred() to signal that an error occurred.

See also: state(), serverName(), waitForConnected()

Definition at line 180 of file qlocalsocket_tcp.cpp.

References ConnectedState, ConnectingState, d, emit, errorOccurred(), QHostAddress::LocalHost, ok, QIODevice::open(), QIODevice::openMode(), OperationError, ServerNotFoundError, QIODevice::setErrorString(), settings, state(), stateChanged(), QVariant::toUInt(), tr, and QSettings::value().

Referenced by connectToServer(), and open().

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◆ disconnected

void QLocalSocket::disconnected ( )

signal

This signal is emitted when the socket has been disconnected.

See also: connectToServer(), disconnectFromServer(), abort(), connected()

◆ disconnectFromServer()

void QLocalSocket::disconnectFromServer ( )

Attempts to close the socket.

If there is pending data waiting to be written, QLocalSocket will enter ClosingState and wait until all data has been written. Eventually, it will enter UnconnectedState and emit the disconnected() signal.

See also: connectToServer()

Definition at line 335 of file qlocalsocket_tcp.cpp.

References d.

◆ error()

QLocalSocket::LocalSocketError QLocalSocket::error ( ) const

◆ errorOccurred

void QLocalSocket::errorOccurred ( QLocalSocket::LocalSocketError socketError )

signal

Since: 5.15

This signal is emitted after an error occurred. The socketError parameter describes the type of error that occurred.

QLocalSocket::LocalSocketError is not a registered metatype, so for queued connections, you will have to register it with Q_DECLARE_METATYPE() and qRegisterMetaType().

See also: error(), errorString(), {Creating Custom Qt Types}

Referenced by LocalSocketSignalTranslator::LocalSocketSignalTranslator(), and connectToServer().

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◆ flush()

bool QLocalSocket::flush ( )

This function writes as much as possible from the internal write buffer to the socket, without blocking.

If any data was written, this function returns true; otherwise false is returned.

Call this function if you need QLocalSocket to start sending buffered data immediately. The number of bytes successfully written depends on the operating system. In most cases, you do not need to call this function, because QLocalSocket will start sending data automatically once control goes back to the event loop. In the absence of an event loop, call waitForBytesWritten() instead.

See also: write(), waitForBytesWritten()

Definition at line 329 of file qlocalsocket_tcp.cpp.

References d.

Referenced by QLocalClientConnection::flush().

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◆ fullServerName()

QString QLocalSocket::fullServerName ( ) const

Returns the server path that the socket is connected to.

Note: The return value of this function is platform specific.

See also: connectToServer(), serverName()

Definition at line 471 of file qlocalsocket.cpp.

References d.

◆ isSequential()

bool QLocalSocket::isSequential ( ) const

overridevirtual

\reimp

Reimplemented from QIODevice.

Definition at line 490 of file qlocalsocket.cpp.

◆ isValid()

bool QLocalSocket::isValid ( ) const

Returns true if the socket is valid and ready for use; otherwise returns false.

Note: The socket's state must be ConnectedState before reading and writing can occur.

See also: state(), connectToServer()

Definition at line 374 of file qlocalsocket_tcp.cpp.

References d.

◆ open()

bool QLocalSocket::open ( OpenMode openMode = ReadWrite )

overridevirtual

Equivalent to connectToServer(OpenMode mode).

The socket is opened in the given openMode to the server defined by setServerName().

Note that unlike in most other QIODevice subclasses, open() may not open the device directly. The function return false if the socket was already connected or if the server to connect to was not defined and true in any other case. The connected() or errorOccurred() signals will be emitted once the device is actually open (or the connection failed).

See connectToServer() for more details.

Definition at line 379 of file qlocalsocket.cpp.

References connectToServer(), QIODevice::isOpen(), and QIODevice::openMode().

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◆ readBufferSize()

qint64 QLocalSocket::readBufferSize ( ) const

Returns the size of the internal read buffer.

This limits the amount of data that the client can receive before you call read() or readAll(). A read buffer size of 0 (the default) means that the buffer has no size limit, ensuring that no data is lost.

See also: setReadBufferSize(), read()

Definition at line 380 of file qlocalsocket_tcp.cpp.

References d.

◆ readData()

qint64 QLocalSocket::readData	(	char *	data,
		qint64	c
	)

overrideprotectedvirtual

\reimp

Implements QIODevice.

Definition at line 261 of file qlocalsocket_tcp.cpp.

References d.

◆ readLineData()

qint64 QLocalSocket::readLineData	(	char *	data,
		qint64	maxSize
	)

overrideprotectedvirtual

\reimp

Reimplemented from QIODevice.

Definition at line 267 of file qlocalsocket_tcp.cpp.

◆ serverName()

QString QLocalSocket::serverName ( ) const

Returns the name of the peer as specified by setServerName(), or an empty QString if setServerName() has not been called or connectToServer() failed.

See also: connectToServer(), fullServerName()

Definition at line 427 of file qlocalsocket.cpp.

References d.

◆ setReadBufferSize()

void QLocalSocket::setReadBufferSize ( qint64 size )

Sets the size of QLocalSocket's internal read buffer to be size bytes.

If the buffer size is limited to a certain size, QLocalSocket won't buffer more than this size of data. Exceptionally, a buffer size of 0 means that the read buffer is unlimited and all incoming data is buffered. This is the default.

This option is useful if you only read the data at certain points in time (e.g., in a real-time streaming application) or if you want to protect your socket against receiving too much data, which may eventually cause your application to run out of memory.

See also: readBufferSize(), read()

Definition at line 386 of file qlocalsocket_tcp.cpp.

References d.

◆ setServerName()

void QLocalSocket::setServerName ( const QString & name )

Since: 5.1

Set the name of the peer to connect to. On Windows name is the name of a named pipe; on Unix name is the name of a local domain socket.

This function must be called when the socket is not connected.

Definition at line 410 of file qlocalsocket.cpp.

References d, qWarning, and UnconnectedState.

Referenced by connectToServer().

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◆ setSocketDescriptor()

bool QLocalSocket::setSocketDescriptor	(	qintptr	socketDescriptor,
		LocalSocketState	socketState = `ConnectedState`,
		OpenMode	openMode = `ReadWrite`
	)

Initializes QLocalSocket with the native socket descriptor socketDescriptor.

Returns true if socketDescriptor is accepted as a valid socket descriptor; otherwise returns false. The socket is opened in the mode specified by openMode, and enters the socket state specified by socketState.

Note: It is not possible to initialize two local sockets with the same native socket descriptor.

See also: socketDescriptor(), state(), openMode()

Definition at line 215 of file qlocalsocket_tcp.cpp.

References child, QObject::children(), QAbstractSocket::ClosingState, ClosingState, QAbstractSocket::ConnectedState, ConnectedState, QAbstractSocket::ConnectingState, ConnectingState, d, QIODevice::open(), QIODevice::openMode(), QObject::parent(), QAbstractSocket::socketDescriptor(), socketDescriptor(), QAbstractSocket::UnconnectedState, and UnconnectedState.

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◆ setSocketOptions()

void QLocalSocket::setSocketOptions ( SocketOptions option )

Definition at line 448 of file qlocalsocket.cpp.

References d, qWarning, and UnconnectedState.

◆ skipData()

qint64 QLocalSocket::skipData ( qint64 maxSize )

overrideprotectedvirtual

\reimp

Reimplemented from QIODevice.

Definition at line 277 of file qlocalsocket_tcp.cpp.

◆ socketDescriptor()

qintptr QLocalSocket::socketDescriptor ( ) const

Returns the native socket descriptor of the QLocalSocket object if this is available; otherwise returns -1.

The socket descriptor is not available when QLocalSocket is in UnconnectedState. The type of the descriptor depends on the platform:

\list

On Windows, the returned value is a \l{Winsock 2 Socket Handle}.

On INTEGRITY, the returned value is the QTcpSocket socket descriptor and the type is defined by \l{QTcpSocket::socketDescriptor}{socketDescriptor}.

On all other UNIX-like operating systems, the type is a file descriptor representing a socket. \endlist

See also: setSocketDescriptor()

Definition at line 255 of file qlocalsocket_tcp.cpp.

References d.

Referenced by QBluetoothSocketPrivateBluezDBus::localPort(), QBluetoothSocketPrivateBluezDBus::peerPort(), and setSocketDescriptor().

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◆ socketOptions()

QLocalSocket::SocketOptions QLocalSocket::socketOptions ( ) const

Definition at line 442 of file qlocalsocket.cpp.

References d.

◆ state()

QLocalSocket::LocalSocketState QLocalSocket::state ( ) const

Returns the state of the socket.

See also: error()

Definition at line 482 of file qlocalsocket.cpp.

References d.

Referenced by connectToServer(), QLocalClientConnection::isConnected(), waitForConnected(), waitForDisconnected(), and waitForReadyRead().

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◆ stateChanged

void QLocalSocket::stateChanged ( QLocalSocket::LocalSocketState socketState )

signal

This signal is emitted whenever QLocalSocket's state changes.

The socketState parameter is the new state.

QLocalSocket::SocketState is not a registered metatype, so for queued connections, you will have to register it with Q_DECLARE_METATYPE() and qRegisterMetaType().

See also: state(), {Creating Custom Qt Types}

Referenced by LocalSocketSignalTranslator::LocalSocketSignalTranslator(), and connectToServer().

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◆ waitForBytesWritten()

bool QLocalSocket::waitForBytesWritten ( int msecs = 30000 )

overridevirtual

\reimp

Reimplemented from QIODevice.

Definition at line 323 of file qlocalsocket_tcp.cpp.

References d.

Referenced by QLocalClientConnection::disconnect().

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◆ waitForConnected()

bool QLocalSocket::waitForConnected ( int msecs = 30000 )

Waits until the socket is connected, up to msecs milliseconds.

If the connection has been established, this function returns true; otherwise it returns false. In the case where it returns false, you can call error() to determine the cause of the error.

The following example waits up to one second for a connection to be established:

socket->connectToServer("market");
if (socket->waitForConnected(1000))
    qDebug("Connected!");

If msecs is -1, this function will not time out.

See also: connectToServer(), connected()

Definition at line 392 of file qlocalsocket_tcp.cpp.

References ConnectedState, ConnectingState, d, and state().

Referenced by QLocalClientConnection::waitForConnection().

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◆ waitForDisconnected()

bool QLocalSocket::waitForDisconnected ( int msecs = 30000 )

Waits until the socket has disconnected, up to msecs milliseconds.

If the connection was successfully disconnected, this function returns true; otherwise it returns false (if the operation timed out, if an error occurred, or if this QLocalSocket is already disconnected). In the case where it returns false, you can call error() to determine the cause of the error.

The following example waits up to one second for a connection to be closed:

socket->disconnectFromServer();
if (socket->state() == QLocalSocket::UnconnectedState
    || socket->waitForDisconnected(1000)) {
    qDebug("Disconnected!");
}

If msecs is -1, this function will not time out.

See also: disconnectFromServer(), close()

Definition at line 401 of file qlocalsocket_tcp.cpp.

References d, qWarning, state(), and UnconnectedState.

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◆ waitForReadyRead()

bool QLocalSocket::waitForReadyRead ( int msecs = 30000 )

overridevirtual

This function blocks until data is available for reading and the \l{QIODevice::}{readyRead()} signal has been emitted.

The function will timeout after msecs milliseconds; the default timeout is 30000 milliseconds.

The function returns true if data is available for reading; otherwise it returns false (if an error occurred or the operation timed out).

See also: waitForBytesWritten()

Reimplemented from QIODevice.

Definition at line 411 of file qlocalsocket_tcp.cpp.

References d, state(), and UnconnectedState.

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◆ writeData()

qint64 QLocalSocket::writeData	(	const char *	data,
		qint64	c
	)

overrideprotectedvirtual

\reimp

Implements QIODevice.

Definition at line 282 of file qlocalsocket_tcp.cpp.

References d.

Property Documentation

◆ socketOptions

QLocalSocket::socketOptions

readwrite

the socket options.

Since: 6.2

Options must be set while the socket is in \l{UnconnectedState} state.

See also: connectToServer()

Definition at line 133 of file qlocalsocket.h.

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

qtbase/src/network/socket/qlocalsocket.h
qtbase/src/network/socket/qlocalsocket.cpp
qtbase/src/network/socket/qlocalsocket_tcp.cpp
qtbase/src/network/socket/qlocalsocket_unix.cpp
qtbase/src/network/socket/qlocalsocket_win.cpp

Public Types

Signals

Public Member Functions

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ LocalSocketError

◆ LocalSocketState

◆ SocketOption

Constructor & Destructor Documentation

◆ QLocalSocket()

◆ ~QLocalSocket()

Member Function Documentation

◆ abort()

◆ bindableSocketOptions()

◆ bytesAvailable()

◆ bytesToWrite()

◆ canReadLine()

◆ close()

◆ connected

◆ connectToServer() [1/2]

◆ connectToServer() [2/2]

◆ disconnected

◆ disconnectFromServer()

◆ error()

◆ errorOccurred

◆ flush()

◆ fullServerName()

◆ isSequential()

◆ isValid()

◆ open()

◆ readBufferSize()

◆ readData()

◆ readLineData()

◆ serverName()

◆ setReadBufferSize()

◆ setServerName()

◆ setSocketDescriptor()

◆ setSocketOptions()

◆ skipData()

◆ socketDescriptor()

◆ socketOptions()

◆ state()

◆ stateChanged

◆ waitForBytesWritten()

◆ waitForConnected()

◆ waitForDisconnected()

◆ waitForReadyRead()

◆ writeData()

Property Documentation

◆ socketOptions