wxSocketBase Class Reference
[Networking]

#include <wx/socket.h>

Inheritance diagram for wxSocketBase:

List of all members.

Detailed Description

wxSocketBase is the base class for all socket-related objects, and it defines all basic IO functionality.

Note:: (Workaround for implementation limitation for wxWidgets up to 2.5.x) If you want to use sockets or derived classes such as wxFTP in a secondary thread, call wxSocketBase::Initialize() (undocumented) from the main thread before creating any sockets - in wxApp::OnInit() for example. See http://wiki.wxwidgets.org/wiki.pl?WxSocket or http://www.litwindow.com/knowhow/knowhow.html for more details.

Events:

The following event handler macros redirect the events to member function handlers 'func' with prototypes like:

void handlerFuncName(wxSocketEvent& event)

Event macros:

EVT_SOCKET(id, func):
Process a wxEVT_SOCKET event. See wxSocketEventFlags and wxSocketFlags for more info.

Library: wxNet

Category: Networking

See also:: wxSocketEvent, wxSocketClient, wxSocketServer, Sockets Sample, wxSocketFlags, wxSocketEventFlags, wxSocketError


Public Member Functions
Construction and Destruction
	wxSocketBase ()
	~wxSocketBase ()
bool	Destroy ()
Socket State
bool	Error () const
bool	GetLocal (wxSockAddress &addr) const
bool	GetPeer (wxSockAddress &addr) const
long	GetTimeout () const
bool	IsConnected () const
bool	IsData () const
bool	IsDisconnected () const
bool	IsOk () const
wxUint32	LastCount () const
wxSocketError	LastError () const
void	RestoreState ()
void	SaveState ()
Basic I/O
See also: wxSocketServer::WaitForAccept(), wxSocketClient::WaitOnConnect()
void	Close ()
wxSocketBase	Discard ()
wxSocketFlags	GetFlags () const
void	InterruptWait ()
wxSocketBase	Peek (void *buffer, wxUint32 nbytes)
wxSocketBase	Read (void *buffer, wxUint32 nbytes)
wxSocketBase	ReadMsg (void *buffer, wxUint32 nbytes)
void	SetFlags (wxSocketFlags flags)
bool	SetLocal (const wxIPV4address &local)
void	SetTimeout (int seconds)
wxSocketBase	Unread (const void *buffer, wxUint32 nbytes)
bool	Wait (long seconds=-1, long millisecond=0)
bool	WaitForLost (long seconds=-1, long millisecond=0)
bool	WaitForRead (long seconds=-1, long millisecond=0)
bool	WaitForWrite (long seconds=-1, long millisecond=0)
wxSocketBase	Write (const void *buffer, wxUint32 nbytes)
wxSocketBase	WriteMsg (const void *buffer, wxUint32 nbytes)
Handling Socket Events
void *	GetClientData () const
void	Notify (bool notify)
void	SetClientData (void *data)
void	SetEventHandler (wxEvtHandler &handler, int id=-1)
void	SetNotify (wxSocketEventFlags flags)

Constructor & Destructor Documentation

wxSocketBase::wxSocketBase ( )

Default constructor.

Don't use it directly; instead, use wxSocketClient to construct a socket client, or wxSocketServer to construct a socket server.

wxSocketBase::~wxSocketBase ( )

Destructor.

Do not destroy a socket using the delete operator directly; use Destroy() instead. Also, do not create socket objects in the stack.

Member Function Documentation

bool wxSocketBase::Destroy ( )

Destroys the socket safely.

Use this function instead of the delete operator, since otherwise socket events could reach the application even after the socket has been destroyed. To prevent this problem, this function appends the wxSocket to a list of object to be deleted on idle time, after all events have been processed. For the same reason, you should avoid creating socket objects in the stack.

Destroy() calls Close() automatically.

Returns:: Always true.

bool wxSocketBase::Error ( ) const

Returns true if an error occurred in the last IO operation.

Use this function to check for an error condition after one of the following calls: Discard(), Peek(), Read(), ReadMsg(), Unread(), Write(), WriteMsg().

bool wxSocketBase::GetLocal ( wxSockAddress & addr ) const

This function returns the local address field of the socket. The local address field contains the complete local address of the socket (local address, local port, ...).

Returns:: true if no error happened, false otherwise.

bool wxSocketBase::GetPeer ( wxSockAddress & addr ) const

This function returns the peer address field of the socket. The peer address field contains the complete peer host address of the socket (address, port, ...).

Returns:: true if no error happened, false otherwise.

long wxSocketBase::GetTimeout ( ) const

Return the socket timeout in seconds.

The timeout can be set using SetTimeout() and is 10 minutes by default.

bool wxSocketBase::IsConnected ( ) const

Returns true if the socket is connected.

bool wxSocketBase::IsData ( ) const

This function waits until the socket is readable.

This might mean that queued data is available for reading or, for streamed sockets, that the connection has been closed, so that a read operation will complete immediately without blocking (unless the wxSOCKET_WAITALL flag is set, in which case the operation might still block).

bool wxSocketBase::IsDisconnected ( ) const

Returns true if the socket is not connected.

bool wxSocketBase::IsOk ( ) const

Returns true if the socket is initialized and ready and false in other cases.

Remarks:: For wxSocketClient, IsOk() won't return true unless the client is connected to a server. For wxSocketServer, IsOk() will return true if the server could bind to the specified address and is already listening for new connections. IsOk() does not check for IO errors; use Error() instead for that purpose.

wxUint32 wxSocketBase::LastCount ( ) const

Returns the number of bytes read or written by the last IO call.

Use this function to get the number of bytes actually transferred after using one of the following IO calls: Discard(), Peek(), Read(), ReadMsg(), Unread(), Write(), WriteMsg().

wxSocketError wxSocketBase::LastError ( ) const

Returns the last wxSocket error. See wxSocketError .

Note:: This function merely returns the last error code, but it should not be used to determine if an error has occurred (this is because successful operations do not change the LastError value). Use Error() first, in order to determine if the last IO call failed. If this returns true, use LastError() to discover the cause of the error.

void wxSocketBase::RestoreState ( )

This function restores the previous state of the socket, as saved with SaveState().

Calls to SaveState() and RestoreState() can be nested.

See also:: SaveState()

void wxSocketBase::SaveState ( )

This function saves the current state of the socket in a stack. Socket state includes flags, as set with SetFlags(), event mask, as set with SetNotify() and Notify(), user data, as set with SetClientData(). Calls to SaveState and RestoreState can be nested.

See also:: RestoreState()

void wxSocketBase::Close ( )

This function shuts down the socket, disabling further transmission and reception of data; it also disables events for the socket and frees the associated system resources.

Upon socket destruction, Close() is automatically called, so in most cases you won't need to do it yourself, unless you explicitly want to shut down the socket, typically to notify the peer that you are closing the connection.

Remarks:: Although Close() immediately disables events for the socket, it is possible that event messages may be waiting in the application's event queue. The application must therefore be prepared to handle socket event messages even after calling Close().

wxSocketBase wxSocketBase::Discard ( )

This function simply deletes all bytes in the incoming queue. This function always returns immediately and its operation is not affected by IO flags.

Use LastCount() to verify the number of bytes actually discarded.

If you use Error(), it will always return false.

wxSocketFlags wxSocketBase::GetFlags ( ) const

Returns current IO flags, as set with SetFlags()

void wxSocketBase::InterruptWait ( )

Use this function to interrupt any wait operation currently in progress.

Note that this is not intended as a regular way to interrupt a Wait call, but only as an escape mechanism for exceptional situations where it is absolutely necessary to use it, for example to abort an operation due to some exception or abnormal problem. InterruptWait is automatically called when you Close() a socket (and thus also upon socket destruction), so you don't need to use it in these cases.

See also:: Wait(), WaitForLost(), WaitForRead(), WaitForWrite(), wxSocketServer::WaitForAccept(), wxSocketClient::WaitOnConnect()

wxSocketBase wxSocketBase::Peek	(	void *	buffer,
		wxUint32	nbytes
	)

This function peeks a buffer of nbytes bytes from the socket.

Peeking a buffer doesn't delete it from the socket input queue.

Use LastCount() to verify the number of bytes actually peeked.

Use Error() to determine if the operation succeeded.

Parameters:

	buffer	Buffer where to put peeked data.
	nbytes	Number of bytes.

Returns:: Returns a reference to the current object.

Remarks:: The exact behaviour of Peek() depends on the combination of flags being used. For a detailed explanation, see SetFlags()

See also:: Error(), LastError(), LastCount(), SetFlags()

wxSocketBase wxSocketBase::Read	(	void *	buffer,
		wxUint32	nbytes
	)

This function reads a buffer of nbytes bytes from the socket. Use LastCount() to verify the number of bytes actually read. Use Error() to determine if the operation succeeded.

Parameters:

	buffer	Buffer where to put read data.
	nbytes	Number of bytes.

Returns:: Returns a reference to the current object.

Remarks:: The exact behaviour of Read() depends on the combination of flags being used. For a detailed explanation, see SetFlags()

See also:: Error(), LastError(), LastCount(), SetFlags()

wxSocketBase wxSocketBase::ReadMsg	(	void *	buffer,
		wxUint32	nbytes
	)

This function reads a buffer sent by WriteMsg() on a socket. If the buffer passed to the function isn't big enough, the remaining bytes will be discarded. This function always waits for the buffer to be entirely filled, unless an error occurs.

Use LastCount() to verify the number of bytes actually read.

Use Error() to determine if the operation succeeded.

Parameters:

	buffer	Buffer where to put read data.
	nbytes	Size of the buffer.

Returns:: Returns a reference to the current object.

Remarks:: ReadMsg() will behave as if the wxSOCKET_WAITALL flag was always set and it will always ignore the wxSOCKET_NOWAIT flag. The exact behaviour of ReadMsg() depends on the wxSOCKET_BLOCK flag. For a detailed explanation, see SetFlags().

See also:: Error(), LastError(), LastCount(), SetFlags(), WriteMsg()

void wxSocketBase::SetFlags ( wxSocketFlags flags )

Use SetFlags to customize IO operation for this socket. The flags parameter may be a combination of flags ORed together. The following flags can be used:

wxSOCKET_NONE:
Normal functionality.
wxSOCKET_NOWAIT:
Read/write as much data as possible and return immediately.
wxSOCKET_WAITALL:
Wait for all required data to be read/written unless an error occurs.
wxSOCKET_BLOCK:
Block the GUI (do not yield) while reading/writing data.
wxSOCKET_REUSEADDR:
Allows the use of an in-use port (wxServerSocket only).
wxSOCKET_BROADCAST:
Switches the socket to broadcast mode.
wxSOCKET_NOBIND:
Stops the socket from being bound to a specific adapter (normally used in conjunction with wxSOCKET_BROADCAST).

For more information on socket events see wxSocketFlags .

bool wxSocketBase::SetLocal ( const wxIPV4address & local )

This function allows you to set the local address and port, useful when an application needs to reuse a particular port. When a local port is set for a wxSocketClient, bind() will be called before connect().

void wxSocketBase::SetTimeout ( int seconds )

This function sets the default socket timeout in seconds. This timeout applies to all IO calls, and also to the Wait() family of functions if you don't specify a wait interval. Initially, the default timeout is 10 minutes.

wxSocketBase wxSocketBase::Unread	(	const void *	buffer,
		wxUint32	nbytes
	)

This function unreads a buffer. That is, the data in the buffer is put back in the incoming queue. This function is not affected by wxSocket flags.

If you use LastCount(), it will always return nbytes.

If you use Error(), it will always return false.

Parameters:

	buffer	Buffer to be unread.
	nbytes	Number of bytes.

Returns:: Returns a reference to the current object.

See also:: Error(), LastCount(), LastError()

bool wxSocketBase::Wait	(	long	seconds = `-1`,
		long	millisecond = `0`
	)

This function waits until any of the following conditions is true:

The socket becomes readable.
The socket becomes writable.
An ongoing connection request has completed (wxSocketClient only)
An incoming connection request has arrived (wxSocketServer only)
The connection has been closed.

Note that it is recommended to use the individual Wait functions to wait for the required condition, instead of this one.

Parameters:

	seconds	Number of seconds to wait. If -1, it will wait for the default timeout, as set with SetTimeout().
	millisecond	Number of milliseconds to wait.

Returns:: Returns true when any of the above conditions is satisfied, false if the timeout was reached.

See also:: InterruptWait(), wxSocketServer::WaitForAccept(), WaitForLost(), WaitForRead(), WaitForWrite(), wxSocketClient::WaitOnConnect()

bool wxSocketBase::WaitForLost	(	long	seconds = `-1`,
		long	millisecond = `0`
	)

This function waits until the connection is lost. This may happen if the peer gracefully closes the connection or if the connection breaks.

Parameters:

	seconds	Number of seconds to wait. If -1, it will wait for the default timeout, as set with SetTimeout().
	millisecond	Number of milliseconds to wait.

Returns:: Returns true if the connection was lost, false if the timeout was reached.

See also:: InterruptWait(), Wait()

bool wxSocketBase::WaitForRead	(	long	seconds = `-1`,
		long	millisecond = `0`
	)

This function waits until the socket is readable.

This might mean that queued data is available for reading or, for streamed sockets, that the connection has been closed, so that a read operation will complete immediately without blocking (unless the wxSOCKET_WAITALL flag is set, in which case the operation might still block).

Parameters:

	seconds	Number of seconds to wait. If -1, it will wait for the default timeout, as set with SetTimeout().
	millisecond	Number of milliseconds to wait.

Returns:: Returns true if the socket becomes readable, false on timeout.

See also:: InterruptWait(), Wait()

bool wxSocketBase::WaitForWrite	(	long	seconds = `-1`,
		long	millisecond = `0`
	)

This function waits until the socket becomes writable.

This might mean that the socket is ready to send new data, or for streamed sockets, that the connection has been closed, so that a write operation is guaranteed to complete immediately (unless the wxSOCKET_WAITALL flag is set, in which case the operation might still block).

Parameters:

	seconds	Number of seconds to wait. If -1, it will wait for the default timeout, as set with SetTimeout().
	millisecond	Number of milliseconds to wait.

Returns:: Returns true if the socket becomes writable, false on timeout.

See also:: InterruptWait(), Wait()

wxSocketBase wxSocketBase::Write	(	const void *	buffer,
		wxUint32	nbytes
	)

This function writes a buffer of nbytes bytes to the socket.

Use LastCount() to verify the number of bytes actually written.

Use Error() to determine if the operation succeeded.

Parameters:

	buffer	Buffer with the data to be sent.
	nbytes	Number of bytes.

Returns:: Returns a reference to the current object.

Remarks:

The exact behaviour of Write() depends on the combination of flags being used. For a detailed explanation, see SetFlags().

See also:: Error(), LastError(), LastCount(), SetFlags()

wxSocketBase wxSocketBase::WriteMsg	(	const void *	buffer,
		wxUint32	nbytes
	)

This function writes a buffer of nbytes bytes from the socket, but it writes a short header before so that ReadMsg() knows how much data should it actually read. So, a buffer sent with WriteMsg() MUST be read with ReadMsg().

This function always waits for the entire buffer to be sent, unless an error occurs.

Use LastCount() to verify the number of bytes actually written.

Use Error() to determine if the operation succeeded.

Parameters:

	buffer	Buffer with the data to be sent.
	nbytes	Number of bytes to send.

Returns:: Returns a reference to the current object.

Remarks:

WriteMsg() will behave as if the wxSOCKET_WAITALL flag was always set and it will always ignore the wxSOCKET_NOWAIT flag. The exact behaviour of WriteMsg() depends on the wxSOCKET_BLOCK flag. For a detailed explanation, see SetFlags().

See also:: Error(), LastError(), LastCount(), SetFlags(), ReadMsg()

void* wxSocketBase::GetClientData ( ) const

Returns a pointer of the client data for this socket, as set with SetClientData()

void wxSocketBase::Notify ( bool notify )

According to the notify value, this function enables or disables socket events. If notify is true, the events configured with SetNotify() will be sent to the application. If notify is false; no events will be sent.

void wxSocketBase::SetClientData ( void * data )

Sets user-supplied client data for this socket. All socket events will contain a pointer to this data, which can be retrieved with the wxSocketEvent::GetClientData() function.

void wxSocketBase::SetEventHandler	(	wxEvtHandler &	handler,
		int	id = `-1`
	)

Sets an event handler to be called when a socket event occurs. The handler will be called for those events for which notification is enabled with SetNotify() and Notify().

Parameters:

	handler	Specifies the event handler you want to use.
	id	The id of socket event.

See also:: SetNotify(), Notify(), wxSocketEvent, wxEvtHandler

void wxSocketBase::SetNotify ( wxSocketEventFlags flags )

Specifies which socket events are to be sent to the event handler. The flags parameter may be combination of flags ORed together. The following flags can be used:

wxSOCKET_INPUT_FLAG:
to receive wxSOCKET_INPUT.
wxSOCKET_OUTPUT_FLAG:
to receive wxSOCKET_OUTPUT.
wxSOCKET_CONNECTION_FLAG:
to receive wxSOCKET_CONNECTION.
wxSOCKET_LOST_FLAG:
to receive wxSOCKET_LOST.

For example:

        sock.SetNotify(wxSOCKET_INPUT_FLAG | wxSOCKET_LOST_FLAG);
        sock.Notify(true);

In this example, the user will be notified about incoming socket data and whenever the connection is closed.

For more information on socket events see wxSocketEventFlags .

wxSocketBase Class Reference [Networking]

Detailed Description

Public Member Functions

Constructor & Destructor Documentation

Member Function Documentation

wxSocketBase Class Reference
[Networking]