glibmm: Gio::Socket Class Reference

Low-level socket object. More...

#include </home/kjell/checkout/gnome/glibmm/gio/giomm/socket.h>

Inheritance diagram for Gio::Socket:

Public Types

- Public Types inherited from Glib::Object
using DestroyNotify = void(*)(gpointer data)
 
- Public Types inherited from sigc::trackable
typedef internal::func_destroy_notify func_destroy_notify
 
- Public Types inherited from sigc::notifiable
typedef internal::func_destroy_notify func_destroy_notify
 

Public Member Functions

 Socket (Socket&& src) noexcept
 
Socketoperator= (Socket&& src) noexcept
 
 ~Socket () noexcept override
 
GSocket* gobj ()
 Provides access to the underlying C GObject. More...

 
const GSocket* gobj () const
 Provides access to the underlying C GObject. More...

 
GSocket* gobj_copy ()
 Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...

 
void bind (const Glib::RefPtr< SocketAddress >& address, bool allow_reuse)
 When a socket is created it is attached to an address family, but it doesn't have an address in this family. More...

 
void listen ()
 Marks the socket as a server socket - a socket that is used to accept incoming requests using Socket::accept(). More...

 
Glib::RefPtr< Socketaccept (const Glib::RefPtr< Cancellable >& cancellable)
 Accept incoming connections on a connection-based socket. More...

 
Glib::RefPtr< Socketaccept ()
 A accept() convenience overload. More...

 
void connect (const Glib::RefPtr< SocketAddress >& address, const Glib::RefPtr< Cancellable >& cancellable)
 Connect the socket to the specified remote address. More...

 
void connect (const Glib::RefPtr< SocketAddress >& address)
 A connect() convenience overload. More...

 
void check_connect_result ()
 Checks and resets the pending connect error for the socket. More...

 
gssize receive (char* buffer, gsize size, const Glib::RefPtr< Cancellable >& cancellable)
 Receive data (up to size bytes) from a socket. More...

 
gssize receive (char* buffer, gsize size)
 A receive() convenience overload. More...

 
gssize receive_from (Glib::RefPtr< SocketAddress >& address, char* buffer, gsize size, const Glib::RefPtr< Cancellable >& cancellable)
 
gssize receive_from (Glib::RefPtr< SocketAddress >& address, char* buffer, gsize size)
 
gssize send (const gchar* buffer, gsize size, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to send size bytes from buffer on the socket. More...

 
gssize send (const gchar* buffer, gsize size)
 A send() convenience overload. More...

 
gssize send_to (const Glib::RefPtr< SocketAddress >& address, const char* buffer, gsize size, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to send size bytes from buffer to address. More...

 
gssize send_to (const Glib::RefPtr< SocketAddress >& address, const char* buffer, gsize size)
 A send_to() convenience overload. More...

 
void close ()
 Closes the socket, shutting down any active connection. More...

 
bool is_closed ()
 Checks whether a socket is closed. More...

 
Glib::RefPtr< SocketSourcecreate_source (Glib::IOCondition condition, const Glib::RefPtr< Cancellable >& cancellable={})
 Creates a SocketSource that can be attached to a Glib::MainContext to monitor for the availability of the specified condition on the socket. More...

 
void shutdown (bool shutdown_read, bool shutdown_write)
 Shut down part or all of a full-duplex connection. More...

 
bool is_connected ()
 Check whether the socket is connected. More...

 
gssize get_available_bytes () const
 Get the amount of data pending in the OS input buffer, without blocking. More...

 
Glib::IOCondition condition_check (Glib::IOCondition condition)
 Checks on the readiness of socket to perform operations. More...

 
void condition_wait (Glib::IOCondition condition, const Glib::RefPtr< Cancellable >& cancellable)
 Waits for condition to become true on socket. More...

 
void condition_wait (Glib::IOCondition condition)
 A condition_wait() convenience overload. More...

 
void condition_timed_wait (Glib::IOCondition condition, gint64 timeout, const Glib::RefPtr< Cancellable >& cancellable)
 Waits for up to timeout microseconds for condition to become true on socket. More...

 
void condition_timed_wait (Glib::IOCondition condition, gint64 timeout)
 A condition_timed_wait() convenience overload. More...

 
void set_listen_backlog (int backlog)
 Sets the maximum number of outstanding connections allowed when listening on this socket. More...

 
int get_listen_backlog () const
 Gets the listen backlog setting of the socket. More...

 
void set_blocking (bool blocking)
 Sets the blocking mode of the socket. More...

 
bool get_blocking () const
 Gets the blocking mode of the socket. More...

 
void set_keepalive (bool keepalive)
 Sets or unsets the SO_KEEPALIVE flag on the underlying socket. More...

 
bool get_keepalive () const
 Gets the keepalive mode of the socket. More...

 
SocketFamily get_family () const
 Gets the socket family of the socket. More...

 
int get_fd () const
 Returns the underlying OS socket object. More...

 
Glib::RefPtr< SocketAddressget_local_address () const
 Try to get the local address of a bound socket. More...

 
Glib::RefPtr< SocketAddressget_remote_address () const
 Try to get the remote address of a connected socket. More...

 
Protocol get_protocol () const
 Gets the socket protocol id the socket was created with. More...

 
Type get_socket_type () const
 Gets the socket type of the socket. More...

 
bool speaks_ipv4 () const
 Checks if a socket is capable of speaking IPv4. More...

 
Glib::RefPtr< Credentialsget_credentials ()
 Returns the credentials of the foreign process connected to this socket, if any (e.g. it is only supported for Gio::SocketFamily::UNIX sockets). More...

 
Glib::RefPtr< const Credentialsget_credentials () const
 Returns the credentials of the foreign process connected to this socket, if any (e.g. it is only supported for Gio::SocketFamily::UNIX sockets). More...

 
guint get_timeout () const
 Gets the timeout setting of the socket. More...

 
void set_timeout (guint timeout)
 Sets the time in seconds after which I/O operations on socket will time out if they have not yet completed. More...

 
gssize receive_with_blocking (gchar* buffer, gsize size, bool blocking, const Glib::RefPtr< Cancellable >& cancellable={})
 This behaves exactly the same as g_socket_receive(), except that the choice of blocking or non-blocking behavior is determined by the blocking argument rather than by socket's properties. More...

 
gssize send_with_blocking (gchar* buffer, gsize size, bool blocking, const Glib::RefPtr< Cancellable >& cancellable={})
 This behaves exactly the same as g_socket_send(), except that the choice of blocking or non-blocking behavior is determined by the blocking argument rather than by socket's properties. More...

 
bool get_option (int level, int optname, int& value) const
 Gets the value of an integer-valued option on socket, as with getsockopt(). More...

 
bool set_option (int level, int optname, int value)
 Sets the value of an integer-valued option on socket, as with setsockopt(). More...

 
guint get_ttl () const
 Gets the unicast time-to-live setting on socket; see g_socket_set_ttl() for more details. More...

 
void set_ttl (guint ttl)
 Sets the time-to-live for outgoing unicast packets on socket. More...

 
bool get_broadcast () const
 Gets the broadcast setting on socket; if true, it is possible to send packets to broadcast addresses. More...

 
void set_broadcast (bool broadcast)
 Sets whether socket should allow sending to broadcast addresses. More...

 
bool get_multicast_loopback () const
 Gets the multicast loopback setting on socket; if true (the default), outgoing multicast packets will be looped back to multicast listeners on the same host. More...

 
void set_multicast_loopback (bool loopback)
 Sets whether outgoing multicast packets will be received by sockets listening on that multicast address on the same host. More...

 
guint get_multicast_ttl () const
 Gets the multicast time-to-live setting on socket; see g_socket_set_multicast_ttl() for more details. More...

 
void set_multicast_ttl (guint ttl)
 Sets the time-to-live for outgoing multicast datagrams on socket. More...

 
bool join_multicast_group (const Glib::RefPtr< InetAddress >& group, bool source_specific, const std::string& iface)
 Registers socket to receive multicast messages sent to group. More...

 
bool join_multicast_group (const Glib::RefPtr< InetAddress >& group, bool source_specific)
 A join_multicast_group() convenience overload. More...

 
bool leave_multicast_group (const Glib::RefPtr< InetAddress >& group, bool source_specific, const std::string& iface)
 Removes socket from the multicast group defined by group, iface, and source_specific (which must all have the same values they had when you joined the group). More...

 
bool leave_multicast_group (const Glib::RefPtr< InetAddress >& group, bool source_specific)
 A leave_multicast_group() convenience overload. More...

 
Glib::PropertyProxy< bool > property_blocking ()
 Whether or not I/O on this socket is blocking. More...

 
Glib::PropertyProxy_ReadOnly< bool > property_blocking () const
 Whether or not I/O on this socket is blocking. More...

 
Glib::PropertyProxy_ReadOnly< SocketFamilyproperty_family () const
 The sockets address family. More...

 
Glib::PropertyProxy_ReadOnly< int > property_fd () const
 The sockets file descriptor. More...

 
Glib::PropertyProxy< bool > property_keepalive ()
 Keep connection alive by sending periodic pings. More...

 
Glib::PropertyProxy_ReadOnly< bool > property_keepalive () const
 Keep connection alive by sending periodic pings. More...

 
Glib::PropertyProxy< int > property_listen_backlog ()
 Outstanding connections in the listen queue. More...

 
Glib::PropertyProxy_ReadOnly< int > property_listen_backlog () const
 Outstanding connections in the listen queue. More...

 
Glib::PropertyProxy_ReadOnly< Glib::RefPtr< SocketAddress > > property_local_address () const
 The local address the socket is bound to. More...

 
Glib::PropertyProxy_ReadOnly< Glib::RefPtr< SocketAddress > > property_remote_address () const
 The remote address the socket is connected to. More...

 
Glib::PropertyProxy< guint > property_timeout ()
 The timeout in seconds on socket I/O. More...

 
Glib::PropertyProxy_ReadOnly< guint > property_timeout () const
 The timeout in seconds on socket I/O. More...

 
Glib::PropertyProxy_ReadOnly< Protocolproperty_protocol () const
 The id of the protocol to use, or -1 for unknown. More...

 
Glib::PropertyProxy< bool > property_broadcast ()
 Whether the socket should allow sending to broadcast addresses. More...

 
Glib::PropertyProxy_ReadOnly< bool > property_broadcast () const
 Whether the socket should allow sending to broadcast addresses. More...

 
Glib::PropertyProxy_ReadOnly< Typeproperty_type () const
 The sockets type. More...

 
Glib::PropertyProxy< guint > property_ttl ()
 Time-to-live for outgoing unicast packets. More...

 
Glib::PropertyProxy_ReadOnly< guint > property_ttl () const
 Time-to-live for outgoing unicast packets. More...

 
Glib::PropertyProxy< bool > property_multicast_loopback ()
 Whether outgoing multicast packets loop back to the local host. More...

 
Glib::PropertyProxy_ReadOnly< bool > property_multicast_loopback () const
 Whether outgoing multicast packets loop back to the local host. More...

 
Glib::PropertyProxy< guint > property_multicast_ttl ()
 Time-to-live out outgoing multicast packets. More...

 
Glib::PropertyProxy_ReadOnly< guint > property_multicast_ttl () const
 Time-to-live out outgoing multicast packets. More...

 
- Public Member Functions inherited from Glib::Object
 Object (const Object&)=delete
 
Objectoperator= (const Object&)=delete
 
 Object (Object&& src) noexcept
 
Objectoperator= (Object&& src) noexcept
 
void* get_data (const QueryQuark& key)
 
void set_data (const Quark& key, void* data)
 
void set_data (const Quark& key, void* data, DestroyNotify notify)
 
void remove_data (const QueryQuark& quark)
 
void* steal_data (const QueryQuark& quark)
 
- Public Member Functions inherited from Glib::ObjectBase
 ObjectBase (const ObjectBase&)=delete
 
ObjectBaseoperator= (const ObjectBase&)=delete
 
void set_property_value (const Glib::ustring& property_name, const Glib::ValueBase& value)
 You probably want to use a specific property_*() accessor method instead. More...

 
void get_property_value (const Glib::ustring& property_name, Glib::ValueBase& value) const
 You probably want to use a specific property_*() accessor method instead. More...

 
template<class PropertyType >
void set_property (const Glib::ustring& property_name, const PropertyType& value)
 You probably want to use a specific property_*() accessor method instead. More...

 
template<class PropertyType >
void get_property (const Glib::ustring& property_name, PropertyType& value) const
 You probably want to use a specific property_*() accessor method instead. More...

 
template<class PropertyType >
PropertyType get_property (const Glib::ustring& property_name) const
 You probably want to use a specific property_*() accessor method instead. More...

 
sigc::connection connect_property_changed (const Glib::ustring& property_name, const sigc::slot< void()>& slot)
 You can use the signal_changed() signal of the property proxy instead. More...

 
sigc::connection connect_property_changed (const Glib::ustring& property_name, sigc::slot< void()>&& slot)
 You can use the signal_changed() signal of the property proxy instead. More...

 
void freeze_notify ()
 Increases the freeze count on object. More...

 
void thaw_notify ()
 Reverts the effect of a previous call to freeze_notify(). More...

 
virtual void reference () const
 Increment the reference count for this object. More...

 
virtual void unreference () const
 Decrement the reference count for this object. More...

 
GObject* gobj ()
 Provides access to the underlying C GObject. More...

 
const GObject* gobj () const
 Provides access to the underlying C GObject. More...

 
GObject* gobj_copy () const
 Give a ref-ed copy to someone. Use for direct struct access. More...

 
- Public Member Functions inherited from sigc::trackable
 trackable () noexcept
 
 trackable (const trackable &src) noexcept
 
 trackable (trackable &&src) noexcept
 
 ~trackable ()
 
void add_destroy_notify_callback (notifiable *data, func_destroy_notify func) const
 
void notify_callbacks ()
 
trackableoperator= (const trackable &src)
 
trackableoperator= (trackable &&src) noexcept
 
void remove_destroy_notify_callback (notifiable *data) const
 
- Public Member Functions inherited from Gio::Initable
 Initable (Initable&& src) noexcept
 
Initableoperator= (Initable&& src) noexcept
 
 ~Initable () noexcept override
 
GInitable* gobj ()
 Provides access to the underlying C GObject. More...

 
const GInitable* gobj () const
 Provides access to the underlying C GObject. More...

 
- Public Member Functions inherited from Glib::Interface
 Interface ()
 A Default constructor. More...

 
 Interface (Interface&& src) noexcept
 
Interfaceoperator= (Interface&& src) noexcept
 
 Interface (const Glib::Interface_Class& interface_class)
 Called by constructors of derived classes. More...

 
 Interface (GObject* castitem)
 Called by constructors of derived classes. More...

 
 ~Interface () noexcept override
 
 Interface (const Interface&)=delete
 
Interfaceoperator= (const Interface&)=delete
 
GObject* gobj ()
 
const GObject* gobj () const
 

Static Public Member Functions

static GType get_type ()
 Get the GType for this class, for use with the underlying GObject type system. More...

 
static Glib::RefPtr< Socketcreate (SocketFamily family, Type type, Protocol protocol, const Glib::RefPtr< Cancellable >& cancellable={})
 Creates a new Socket with the defined family, type and protocol. More...

 
static Glib::RefPtr< Socketcreate_from_fd (int fd, const Glib::RefPtr< Cancellable >& cancellable={})
 Creates a new Socket from a native file descriptor or winsock SOCKET handle. More...

 
- Static Public Member Functions inherited from Gio::Initable
static void add_interface (GType gtype_implementer)
 
static GType get_type ()
 Get the GType for this class, for use with the underlying GObject type system. More...

 

Protected Member Functions

 Socket (SocketFamily family, Type type, Protocol protocol, const Glib::RefPtr< Cancellable >& cancellable)
 
 Socket (int fd, const Glib::RefPtr< Cancellable >& cancellable)
 
- Protected Member Functions inherited from Glib::Object
 Object ()
 
 Object (const Glib::ConstructParams& construct_params)
 
 Object (GObject* castitem)
 
 ~Object () noexcept override
 
- Protected Member Functions inherited from Glib::ObjectBase
 ObjectBase ()
 This default constructor is called implicitly from the constructor of user-derived classes, even if, for instance, Gtk::Button calls a different ObjectBase constructor. More...

 
 ObjectBase (const char* custom_type_name)
 A derived constructor always overrides this choice. More...

 
 ObjectBase (const std::type_info& custom_type_info)
 This constructor is a special feature to allow creation of derived types on the fly, without having to use g_object_new() manually. More...

 
 ObjectBase (ObjectBase&& src) noexcept
 
ObjectBaseoperator= (ObjectBase&& src) noexcept
 
virtual ~ObjectBase () noexcept=0
 
void initialize (GObject* castitem)
 
void initialize_move (GObject* castitem, Glib::ObjectBase* previous_wrapper)
 
- Protected Member Functions inherited from Gio::Initable
 Initable ()
 You should derive from this class to use it. More...

 
void init (const Glib::RefPtr< Cancellable >& cancellable)
 Initializes the object implementing the interface. More...

 
void init ()
 A init() convenience overload. More...

 
virtual bool init_vfunc (const Glib::RefPtr< Cancellable >& cancellable, GError** error)
 

Related Functions

(Note that these are not member functions.)

Glib::RefPtr< Gio::Socketwrap (GSocket* object, bool take_copy=false)
 A Glib::wrap() method for this object. More...

 

Detailed Description

Low-level socket object.

A Socket is a low-level networking primitive. It is a more or less direct mapping of the BSD socket API in a portable GObject based API. It supports both the UNIX socket implementations and winsock2 on Windows.

Socket is the platform independent base upon which the higher level network primitives are based. Applications are not typically meant to use it directly, but rather through classes like SocketClient, SocketService and SocketConnection. However there may be cases where direct use of Socket is useful.

Socket implements the Initable interface, and since initialization can fail, the constructor may throw an exception.

Sockets operate in two general modes, blocking or non-blocking. When in blocking mode all operations block until the requested operation is finished or there is an error. In non-blocking mode all calls that would block return immediately with a Gio::Error::WOULD_BLOCK error. To know when a call would successfully run you can call condition_check(), or condition_wait(). You can also use create_source() and attach it to a Glib::MainContext to get callbacks when I/O is possible. Note that all sockets are always set to non blocking mode in the system, and blocking mode is emulated in Socket.

When working in non-blocking mode applications should always be able to handle getting a Gio::Error::WOULD_BLOCK error even when some other function said that I/O was possible. This can easily happen in case of a race condition in the application, but it can also happen for other reasons. For instance, on Windows a socket is always seen as writable until a write returns Gio::Error::WOULD_BLOCK.

Sockets can be either connection oriented or datagram based. For connection oriented types you must first establish a connection by either connecting to an address or accepting a connection from another address. For connectionless socket types the target/source address is specified or received in each I/O operation.

All socket file descriptors are set to be close-on-exec.

Note that creating a Socket causes the signal SIGPIPE to be ignored for the remainder of the program. If you are writing a command-line utility that uses Socket, you may need to take into account the fact that your program will not automatically be killed if it tries to write to stdout after it has been closed.

Since glibmm 2.24:

Constructor & Destructor Documentation

Gio::Socket::Socket ( Socket&&  src)
noexcept
Gio::Socket::~Socket ( )
overridenoexcept
Gio::Socket::Socket ( SocketFamily  family,
Type  type,
Protocol  protocol,
const Glib::RefPtr< Cancellable >&  cancellable 
)
protected
Gio::Socket::Socket ( int  fd,
const Glib::RefPtr< Cancellable >&  cancellable 
)
protected

Member Function Documentation

Glib::RefPtr<Socket> Gio::Socket::accept ( const Glib::RefPtr< Cancellable >&  cancellable)

Accept incoming connections on a connection-based socket.

This removes the first outstanding connection request from the listening socket and creates a GSocket object for it.

The socket must be bound to a local address with g_socket_bind() and must be listening for incoming connections (Socket::listen()).

If there are no outstanding connections then the operation will block or throw Gio::Error with ERROR_WOULD_BLOCK if non-blocking I/O is enabled. To be notified of an incoming connection, wait for the Glib::IO_IN condition.

Parameters
cancellableA Cancellable object which can be used to cancel the operation.
Returns
a Gio::Socket
Exceptions
Gio::Error
Glib::RefPtr<Socket> Gio::Socket::accept ( )

A accept() convenience overload.

void Gio::Socket::bind ( const Glib::RefPtr< SocketAddress >&  address,
bool  allow_reuse 
)

When a socket is created it is attached to an address family, but it doesn't have an address in this family.

Socket::bind() assigns the address (sometimes called name) of the socket.

It is generally required to bind to a local address before you can receive connections. (See Socket::listen() and Socket::accept()). In certain situations, you may also want to bind a socket that will be used to initiate connections, though this is not normally required.

If socket is a TCP socket, then allow_reuse controls the setting of the SO_REUSEADDR socket option; normally it should be true for server sockets (sockets that you will eventually call Socket::accept() on), and false for client sockets. (Failing to set this flag on a server socket may cause Socket::bind() to throw Gio::Error with ADDRESS_IN_USE if the server program is stopped and then immediately restarted.)

If socket is a UDP socket, then allow_reuse determines whether or not other UDP sockets can be bound to the same address at the same time. In particular, you can have several UDP sockets bound to the same address, and they will all receive all of the multicast and broadcast packets sent to that address. (The behavior of unicast UDP packets to an address with multiple listeners is not defined.)

Parameters
addressa SocketAddress specifying the local address.
allow_reusewhether to allow reusing this address
Exceptions
Gio::Error
void Gio::Socket::check_connect_result ( )

Checks and resets the pending connect error for the socket.

This is used to check for errors when g_socket_connect() is used in non-blocking mode.

Since glibmm 2.22:
Exceptions
Glib::Error
void Gio::Socket::close ( )

Closes the socket, shutting down any active connection.

Closing a socket does not wait for all outstanding I/O operations to finish, so the caller should not rely on them to be guaranteed to complete even if the close returns with no error.

Once the socket is closed, all other operations will return Gio::Error::CLOSED. Closing a socket multiple times will not return an error.

Sockets will be automatically closed when the last reference is dropped, but you might want to call this function to make sure resources are released as early as possible.

Beware that due to the way that TCP works, it is possible for recently-sent data to be lost if either you close a socket while the Glib::IOCondition::IN condition is set, or else if the remote connection tries to send something to you after you close the socket but before it has finished reading all of the data you sent. There is no easy generic way to avoid this problem; the easiest fix is to design the network protocol such that the client will never send data "out of turn". Another solution is for the server to half-close the connection by calling g_socket_shutdown() with only the shutdown_write flag set, and then wait for the client to notice this and close its side of the connection, after which the server can safely call g_socket_close(). (This is what TcpConnection does if you call g_tcp_connection_set_graceful_disconnect(). But of course, this only works if the client will close its connection after the server does.)

Since glibmm 2.22:
Exceptions
Glib::Error
Glib::IOCondition Gio::Socket::condition_check ( Glib::IOCondition  condition)

Checks on the readiness of socket to perform operations.

The operations specified in condition are checked for and masked against the currently-satisfied conditions on socket. The result is returned.

Note that on Windows, it is possible for an operation to return Gio::Error::WOULD_BLOCK even immediately after g_socket_condition_check() has claimed that the socket is ready for writing. Rather than calling g_socket_condition_check() and then writing to the socket if it succeeds, it is generally better to simply try writing to the socket right away, and try again later if the initial attempt returns Gio::Error::WOULD_BLOCK.

It is meaningless to specify Glib::IOCondition::ERR or Glib::IOCondition::HUP in condition; these conditions will always be set in the output if they are true.

This call never blocks.

Since glibmm 2.22:
Parameters
conditionA IOCondition mask to check.
Returns
The GIOCondition mask of the current state.
void Gio::Socket::condition_timed_wait ( Glib::IOCondition  condition,
gint64  timeout,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Waits for up to timeout microseconds for condition to become true on socket.

If the condition is met, true is returned.

If cancellable is cancelled before the condition is met, or if timeout (or the socket's Socket::property_timeout()) is reached before the condition is met, then false is returned and error, if non-nullptr, is set to the appropriate value (Gio::Error::CANCELLED or Gio::Error::TIMED_OUT).

If you don't want a timeout, use g_socket_condition_wait(). (Alternatively, you can pass -1 for timeout.)

Note that although timeout is in microseconds for consistency with other GLib APIs, this function actually only has millisecond resolution, and the behavior is undefined if timeout is not an exact number of milliseconds.

Since glibmm 2.32:
Parameters
conditionA IOCondition mask to wait for.
timeoutThe maximum time (in microseconds) to wait, or -1.
cancellableA Cancellable, or nullptr.
Exceptions
Glib::Error
void Gio::Socket::condition_timed_wait ( Glib::IOCondition  condition,
gint64  timeout 
)

A condition_timed_wait() convenience overload.

void Gio::Socket::condition_wait ( Glib::IOCondition  condition,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Waits for condition to become true on socket.

When the condition is met, true is returned.

If cancellable is cancelled before the condition is met, or if the socket has a timeout set and it is reached before the condition is met, then false is returned and error, if non-nullptr, is set to the appropriate value (Gio::Error::CANCELLED or Gio::Error::TIMED_OUT).

See also g_socket_condition_timed_wait().

Since glibmm 2.22:
Parameters
conditionA IOCondition mask to wait for.
cancellableA Cancellable, or nullptr.
Exceptions
Glib::Error
void Gio::Socket::condition_wait ( Glib::IOCondition  condition)

A condition_wait() convenience overload.

void Gio::Socket::connect ( const Glib::RefPtr< SocketAddress >&  address,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Connect the socket to the specified remote address.

For connection oriented socket this generally means we attempt to make a connection to the address . For a connection-less socket it sets the default address for Socket::send() and discards all incoming datagrams from other sources.

Generally connection oriented sockets can only connect once, but connection-less sockets can connect multiple times to change the default address.

If the connect call needs to do network I/O it will block, unless non-blocking I/O is enabled. Then Gio::Error with ERROR_PENDING is thrown and the user can be notified of the connection finishing by waiting for the Glib::IO_OUT condition. The result of the connection must then be checked with Socket::check_connect_result().

Parameters
addressa SocketAddress specifying the remote address.
cancellableA Cancellable object which can be used to cancel the operation.
Exceptions
Gio::Error
void Gio::Socket::connect ( const Glib::RefPtr< SocketAddress >&  address)

A connect() convenience overload.

static Glib::RefPtr<Socket> Gio::Socket::create ( SocketFamily  family,
Type  type,
Protocol  protocol,
const Glib::RefPtr< Cancellable >&  cancellable = {} 
)
static

Creates a new Socket with the defined family, type and protocol.

If protocol is 0 (Gio::Socket::Protocol::DEFAULT) the default protocol type for the family and type is used.

The protocol is a family and type specific int that specifies what kind of protocol to use. Gio::Socket::Protocol lists several common ones. Many families only support one protocol, and use 0 for this, others support several and using 0 means to use the default protocol for the family and type.

The protocol id is passed directly to the operating system, so you can use protocols not listed in Gio::Socket::Protocol if you know the protocol number used for it.

Since glibmm 2.22:
Parameters
familyThe socket family to use, e.g. Gio::SocketFamily::IPV4.
typeThe socket type to use.
protocolThe id of the protocol to use, or 0 for default.
Returns
A Socket or nullptr on error. Free the returned object with Glib::object_unref().
Parameters
cancellableA Cancellable object which can be used to cancel the operation.
Exceptions
Glib::Error
static Glib::RefPtr<Socket> Gio::Socket::create_from_fd ( int  fd,
const Glib::RefPtr< Cancellable >&  cancellable = {} 
)
static

Creates a new Socket from a native file descriptor or winsock SOCKET handle.

This reads all the settings from the file descriptor so that all properties should work. Note that the file descriptor will be set to non-blocking mode, independent on the blocking mode of the Socket.

On success, the returned Socket takes ownership of fd. On failure, the caller must close fd themselves.

Since GLib 2.46, it is no longer a fatal error to call this on a non-socket descriptor. Instead, a GError will be set with code Gio::Error::FAILED

Since glibmm 2.22:
Parameters
fdA native socket file descriptor.
Returns
A Socket or nullptr on error. Free the returned object with Glib::object_unref().
Parameters
cancellableA Cancellable object which can be used to cancel the operation.
Exceptions
Glib::Error
Glib::RefPtr<SocketSource> Gio::Socket::create_source ( Glib::IOCondition  condition,
const Glib::RefPtr< Cancellable >&  cancellable = {} 
)

Creates a SocketSource that can be attached to a Glib::MainContext to monitor for the availability of the specified condition on the socket.

Create a slot from a function to be called when condition is met for the socket with sigc::ptr_fun() or sigc::mem_fun() and pass it into the connect() function of the returned SocketSource object. Polling of the socket will start when you attach a Glib::MainContext object to the returned SocketSource object using its attach() function.

It is meaningless to specify Glib::IO_ERR or Glib::IO_HUP in condition; these conditions will always be reported output if they are true.

cancellable can be used to cancel the source, which will cause the source to trigger, reporting the current condition (which is likely 0 unless cancellation happened at the same time as a condition change). You can check for this in the callback using Cancellable::is_cancelled().

If the socket has a timeout set, and it is reached before condition occurs, the source will then trigger anyway, reporting Glib::IO_IN or Glib::IO_OUT depending on condition. However, the socket will have been marked as having had a timeout, and so the next Socket I/O method you call will then fail with a Gio::IO_ERROR_TIMED_OUT.

Gio::signal_socket().connect() is a simpler interface to the same functionality.

Since glibmm 2.42:
Parameters
conditionA Glib::IOCondition mask to monitor.
cancellableA Cancellable. The default value means the source is not cancellable.
Returns
A newly allocated SocketSource.
gssize Gio::Socket::get_available_bytes ( ) const

Get the amount of data pending in the OS input buffer, without blocking.

If socket is a UDP or SCTP socket, this will return the size of just the next packet, even if additional packets are buffered after that one.

Note that on Windows, this function is rather inefficient in the UDP case, and so if you know any plausible upper bound on the size of the incoming packet, it is better to just do a g_socket_receive() with a buffer of that size, rather than calling g_socket_get_available_bytes() first and then doing a receive of exactly the right size.

Since glibmm 2.32:
Returns
The number of bytes that can be read from the socket without blocking or truncating, or -1 on error.
bool Gio::Socket::get_blocking ( ) const

Gets the blocking mode of the socket.

For details on blocking I/O, see g_socket_set_blocking().

Since glibmm 2.22:
Returns
true if blocking I/O is used, false otherwise.
bool Gio::Socket::get_broadcast ( ) const

Gets the broadcast setting on socket; if true, it is possible to send packets to broadcast addresses.

Since glibmm 2.32:
Returns
The broadcast setting on socket.
Glib::RefPtr<Credentials> Gio::Socket::get_credentials ( )

Returns the credentials of the foreign process connected to this socket, if any (e.g. it is only supported for Gio::SocketFamily::UNIX sockets).

If this operation isn't supported on the OS, the method fails with the Gio::Error::NOT_SUPPORTED error. On Linux this is implemented by reading the SO_PEERCRED option on the underlying socket.

Other ways to obtain credentials from a foreign peer includes the UnixCredentialsMessage type and g_unix_connection_send_credentials() / g_unix_connection_receive_credentials() functions.

Since glibmm 2.26:
Returns
nullptr if error is set, otherwise a Credentials object that must be freed with Glib::object_unref().
Exceptions
Glib::Error
Glib::RefPtr<const Credentials> Gio::Socket::get_credentials ( ) const

Returns the credentials of the foreign process connected to this socket, if any (e.g. it is only supported for Gio::SocketFamily::UNIX sockets).

If this operation isn't supported on the OS, the method fails with the Gio::Error::NOT_SUPPORTED error. On Linux this is implemented by reading the SO_PEERCRED option on the underlying socket.

Other ways to obtain credentials from a foreign peer includes the UnixCredentialsMessage type and g_unix_connection_send_credentials() / g_unix_connection_receive_credentials() functions.

Since glibmm 2.26:
Returns
nullptr if error is set, otherwise a Credentials object that must be freed with Glib::object_unref().
Exceptions
Glib::Error
SocketFamily Gio::Socket::get_family ( ) const

Gets the socket family of the socket.

Since glibmm 2.22:
Returns
A SocketFamily.
int Gio::Socket::get_fd ( ) const

Returns the underlying OS socket object.

On unix this is a socket file descriptor, and on Windows this is a Winsock2 SOCKET handle. This may be useful for doing platform specific or otherwise unusual operations on the socket.

Since glibmm 2.22:
Returns
The file descriptor of the socket.
bool Gio::Socket::get_keepalive ( ) const

Gets the keepalive mode of the socket.

For details on this, see g_socket_set_keepalive().

Since glibmm 2.22:
Returns
true if keepalive is active, false otherwise.
int Gio::Socket::get_listen_backlog ( ) const

Gets the listen backlog setting of the socket.

For details on this, see g_socket_set_listen_backlog().

Since glibmm 2.22:
Returns
The maximum number of pending connections.
Glib::RefPtr<SocketAddress> Gio::Socket::get_local_address ( ) const

Try to get the local address of a bound socket.

This is only useful if the socket has been bound to a local address, either explicitly or implicitly when connecting.

Since glibmm 2.22:
Returns
A SocketAddress or nullptr on error. Free the returned object with Glib::object_unref().
Exceptions
Glib::Error
bool Gio::Socket::get_multicast_loopback ( ) const

Gets the multicast loopback setting on socket; if true (the default), outgoing multicast packets will be looped back to multicast listeners on the same host.

Since glibmm 2.32:
Returns
The multicast loopback setting on socket.
guint Gio::Socket::get_multicast_ttl ( ) const

Gets the multicast time-to-live setting on socket; see g_socket_set_multicast_ttl() for more details.

Since glibmm 2.32:
Returns
The multicast time-to-live setting on socket.
bool Gio::Socket::get_option ( int  level,
int  optname,
int &  value 
) const

Gets the value of an integer-valued option on socket, as with getsockopt().

(If you need to fetch a non-integer-valued option, you will need to call getsockopt() directly.)

The [<gio/gnetworking.h>][gio-gnetworking.h] header pulls in system headers that will define most of the standard/portable socket options. For unusual socket protocols or platform-dependent options, you may need to include additional headers.

Note that even for socket options that are a single byte in size, value is still a pointer to a int variable, not a #guchar; g_socket_get_option() will handle the conversion internally.

Since glibmm 2.36:
Parameters
levelThe "API level" of the option (eg, SOL_SOCKET).
optnameThe "name" of the option (eg, SO_BROADCAST).
valueReturn location for the option value.
Returns
Success or failure. On failure, error will be set, and the system error value (errno or WSAGetLastError()) will still be set to the result of the getsockopt() call.
Exceptions
Glib::Error
Protocol Gio::Socket::get_protocol ( ) const

Gets the socket protocol id the socket was created with.

In case the protocol is unknown, -1 is returned.

Since glibmm 2.22:
Returns
A protocol id, or -1 if unknown.
Glib::RefPtr<SocketAddress> Gio::Socket::get_remote_address ( ) const

Try to get the remote address of a connected socket.

This is only useful for connection oriented sockets that have been connected.

Since glibmm 2.22:
Returns
A SocketAddress or nullptr on error. Free the returned object with Glib::object_unref().
Exceptions
Glib::Error
Type Gio::Socket::get_socket_type ( ) const

Gets the socket type of the socket.

Since glibmm 2.22:
Returns
A Gio::Socket::Type.
guint Gio::Socket::get_timeout ( ) const

Gets the timeout setting of the socket.

For details on this, see g_socket_set_timeout().

Since glibmm 2.26:
Returns
The timeout in seconds.
guint Gio::Socket::get_ttl ( ) const

Gets the unicast time-to-live setting on socket; see g_socket_set_ttl() for more details.

Since glibmm 2.32:
Returns
The time-to-live setting on socket.
static GType Gio::Socket::get_type ( )
static

Get the GType for this class, for use with the underlying GObject type system.

GSocket* Gio::Socket::gobj ( )
inline

Provides access to the underlying C GObject.

const GSocket* Gio::Socket::gobj ( ) const
inline

Provides access to the underlying C GObject.

GSocket* Gio::Socket::gobj_copy ( )

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

bool Gio::Socket::is_closed ( )

Checks whether a socket is closed.

Since glibmm 2.22:
Returns
true if socket is closed, false otherwise.
bool Gio::Socket::is_connected ( )

Check whether the socket is connected.

This is only useful for connection-oriented sockets.

If using g_socket_shutdown(), this function will return true until the socket has been shut down for reading and writing. If you do a non-blocking connect, this function will not return true until after you call g_socket_check_connect_result().

Since glibmm 2.22:
Returns
true if socket is connected, false otherwise.
bool Gio::Socket::join_multicast_group ( const Glib::RefPtr< InetAddress >&  group,
bool  source_specific,
const std::string iface 
)

Registers socket to receive multicast messages sent to group.

socket must be a Gio::Socket::Type::DATAGRAM socket, and must have been bound to an appropriate interface and port with g_socket_bind().

If iface is nullptr, the system will automatically pick an interface to bind to based on group.

If source_specific is true, source-specific multicast as defined in RFC 4604 is used. Note that on older platforms this may fail with a Gio::Error::NOT_SUPPORTED error.

To bind to a given source-specific multicast address, use g_socket_join_multicast_group_ssm() instead.

Since glibmm 2.32:
Parameters
groupA InetAddress specifying the group address to join.
ifaceName of the interface to use, or nullptr.
source_specifictrue if source-specific multicast should be used.
Returns
true on success, false on error.
Exceptions
Glib::Error
bool Gio::Socket::join_multicast_group ( const Glib::RefPtr< InetAddress >&  group,
bool  source_specific 
)

A join_multicast_group() convenience overload.

bool Gio::Socket::leave_multicast_group ( const Glib::RefPtr< InetAddress >&  group,
bool  source_specific,
const std::string iface 
)

Removes socket from the multicast group defined by group, iface, and source_specific (which must all have the same values they had when you joined the group).

socket remains bound to its address and port, and can still receive unicast messages after calling this.

To unbind to a given source-specific multicast address, use g_socket_leave_multicast_group_ssm() instead.

Since glibmm 2.32:
Parameters
groupA InetAddress specifying the group address to leave.
ifaceInterface used.
source_specifictrue if source-specific multicast was used.
Returns
true on success, false on error.
Exceptions
Glib::Error
bool Gio::Socket::leave_multicast_group ( const Glib::RefPtr< InetAddress >&  group,
bool  source_specific 
)

A leave_multicast_group() convenience overload.

void Gio::Socket::listen ( )

Marks the socket as a server socket - a socket that is used to accept incoming requests using Socket::accept().

Before calling this the socket must be bound to a local address using Socket::bind().

To set the maximum amount of outstanding clients, use Socket::set_listen_backlog().

Exceptions
Gio::Error
Socket& Gio::Socket::operator= ( Socket&&  src)
noexcept
Glib::PropertyProxy< bool > Gio::Socket::property_blocking ( )

Whether or not I/O on this socket is blocking.

Default value: true

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< bool > Gio::Socket::property_blocking ( ) const

Whether or not I/O on this socket is blocking.

Default value: true

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< bool > Gio::Socket::property_broadcast ( )

Whether the socket should allow sending to broadcast addresses.

Since glibmm 2.32:

Default value: false

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< bool > Gio::Socket::property_broadcast ( ) const

Whether the socket should allow sending to broadcast addresses.

Since glibmm 2.32:

Default value: false

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< SocketFamily > Gio::Socket::property_family ( ) const

The sockets address family.

Default value: Gio::SocketFamily::INVALID

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< int > Gio::Socket::property_fd ( ) const

The sockets file descriptor.

Default value: -1

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< bool > Gio::Socket::property_keepalive ( )

Keep connection alive by sending periodic pings.

Default value: false

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< bool > Gio::Socket::property_keepalive ( ) const

Keep connection alive by sending periodic pings.

Default value: false

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< int > Gio::Socket::property_listen_backlog ( )

Outstanding connections in the listen queue.

Default value: 10

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< int > Gio::Socket::property_listen_backlog ( ) const

Outstanding connections in the listen queue.

Default value: 10

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< Glib::RefPtr<SocketAddress> > Gio::Socket::property_local_address ( ) const

The local address the socket is bound to.

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< bool > Gio::Socket::property_multicast_loopback ( )

Whether outgoing multicast packets loop back to the local host.

Since glibmm 2.32:

Default value: true

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< bool > Gio::Socket::property_multicast_loopback ( ) const

Whether outgoing multicast packets loop back to the local host.

Since glibmm 2.32:

Default value: true

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< guint > Gio::Socket::property_multicast_ttl ( )

Time-to-live out outgoing multicast packets.

Since glibmm 2.32:

Default value: 1

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< guint > Gio::Socket::property_multicast_ttl ( ) const

Time-to-live out outgoing multicast packets.

Since glibmm 2.32:

Default value: 1

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< Protocol > Gio::Socket::property_protocol ( ) const

The id of the protocol to use, or -1 for unknown.

Default value: Gio::Socket::Protocol::UNKNOWN

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< Glib::RefPtr<SocketAddress> > Gio::Socket::property_remote_address ( ) const

The remote address the socket is connected to.

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< guint > Gio::Socket::property_timeout ( )

The timeout in seconds on socket I/O.

Since glibmm 2.26:

Default value: 0

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< guint > Gio::Socket::property_timeout ( ) const

The timeout in seconds on socket I/O.

Since glibmm 2.26:

Default value: 0

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy< guint > Gio::Socket::property_ttl ( )

Time-to-live for outgoing unicast packets.

Since glibmm 2.32:

Default value: 0

Returns
A PropertyProxy that allows you to get or set the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< guint > Gio::Socket::property_ttl ( ) const

Time-to-live for outgoing unicast packets.

Since glibmm 2.32:

Default value: 0

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
Glib::PropertyProxy_ReadOnly< Type > Gio::Socket::property_type ( ) const

The sockets type.

Default value: Gio::Socket::Type::STREAM

Returns
A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.
gssize Gio::Socket::receive ( char *  buffer,
gsize  size,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Receive data (up to size bytes) from a socket.

This is mainly used by connection-oriented sockets; it is identical to g_socket_receive_from() with address set to nullptr.

For Gio::Socket::Type::DATAGRAM and Gio::Socket::Type::SEQPACKET sockets, g_socket_receive() will always read either 0 or 1 complete messages from the socket. If the received message is too large to fit in buffer, then the data beyond size bytes will be discarded, without any explicit indication that this has occurred.

For Gio::Socket::Type::STREAM sockets, g_socket_receive() can return any number of bytes, up to size. If more than size bytes have been received, the additional data will be returned in future calls to g_socket_receive().

If the socket is in blocking mode the call will block until there is some data to receive, the connection is closed, or there is an error. If there is no data available and the socket is in non-blocking mode, a Gio::Error::WOULD_BLOCK error will be returned. To be notified when data is available, wait for the Glib::IOCondition::IN condition.

On error -1 is returned and error is set accordingly.

Since glibmm 2.22:
Parameters
bufferA buffer to read data into (which should be at least size bytes long).
sizeThe number of bytes you want to read from the socket.
cancellableA Cancellable or nullptr.
Returns
Number of bytes read, or 0 if the connection was closed by the peer, or -1 on error.
Exceptions
Glib::Error
gssize Gio::Socket::receive ( char *  buffer,
gsize  size 
)

A receive() convenience overload.

gssize Gio::Socket::receive_from ( Glib::RefPtr< SocketAddress >&  address,
char *  buffer,
gsize  size,
const Glib::RefPtr< Cancellable >&  cancellable 
)
gssize Gio::Socket::receive_from ( Glib::RefPtr< SocketAddress >&  address,
char *  buffer,
gsize  size 
)
gssize Gio::Socket::receive_with_blocking ( gchar *  buffer,
gsize  size,
bool  blocking,
const Glib::RefPtr< Cancellable >&  cancellable = {} 
)

This behaves exactly the same as g_socket_receive(), except that the choice of blocking or non-blocking behavior is determined by the blocking argument rather than by socket's properties.

Since glibmm 2.26:
Parameters
bufferA buffer to read data into (which should be at least size bytes long).
sizeThe number of bytes you want to read from the socket.
blockingWhether to do blocking or non-blocking I/O.
cancellableA Cancellable or nullptr.
Returns
Number of bytes read, or 0 if the connection was closed by the peer, or -1 on error.
gssize Gio::Socket::send ( const gchar *  buffer,
gsize  size,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to send size bytes from buffer on the socket.

This is mainly used by connection-oriented sockets; it is identical to g_socket_send_to() with address set to nullptr.

If the socket is in blocking mode the call will block until there is space for the data in the socket queue. If there is no space available and the socket is in non-blocking mode a Gio::Error::WOULD_BLOCK error will be returned. To be notified when space is available, wait for the Glib::IOCondition::OUT condition. Note though that you may still receive Gio::Error::WOULD_BLOCK from g_socket_send() even if you were previously notified of a Glib::IOCondition::OUT condition. (On Windows in particular, this is very common due to the way the underlying APIs work.)

On error -1 is returned and error is set accordingly.

Since glibmm 2.22:
Parameters
bufferThe buffer containing the data to send.
sizeThe number of bytes to send.
cancellableA Cancellable or nullptr.
Returns
Number of bytes written (which may be less than size), or -1 on error.
Exceptions
Glib::Error
gssize Gio::Socket::send ( const gchar *  buffer,
gsize  size 
)

A send() convenience overload.

gssize Gio::Socket::send_to ( const Glib::RefPtr< SocketAddress >&  address,
const char *  buffer,
gsize  size,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to send size bytes from buffer to address.

If address is nullptr then the message is sent to the default receiver (set by g_socket_connect()).

See g_socket_send() for additional information.

Since glibmm 2.22:
Parameters
addressA SocketAddress, or nullptr.
bufferThe buffer containing the data to send.
sizeThe number of bytes to send.
cancellableA Cancellable or nullptr.
Returns
Number of bytes written (which may be less than size), or -1 on error.
Exceptions
Glib::Error
gssize Gio::Socket::send_to ( const Glib::RefPtr< SocketAddress >&  address,
const char *  buffer,
gsize  size 
)

A send_to() convenience overload.

gssize Gio::Socket::send_with_blocking ( gchar *  buffer,
gsize  size,
bool  blocking,
const Glib::RefPtr< Cancellable >&  cancellable = {} 
)

This behaves exactly the same as g_socket_send(), except that the choice of blocking or non-blocking behavior is determined by the blocking argument rather than by socket's properties.

Since glibmm 2.26:
Parameters
bufferThe buffer containing the data to send.
sizeThe number of bytes to send.
blockingWhether to do blocking or non-blocking I/O.
cancellableA Cancellable or nullptr.
Returns
Number of bytes written (which may be less than size), or -1 on error.
void Gio::Socket::set_blocking ( bool  blocking)

Sets the blocking mode of the socket.

In blocking mode all operations (which don’t take an explicit blocking parameter) block until they succeed or there is an error. In non-blocking mode all functions return results immediately or with a Gio::Error::WOULD_BLOCK error.

All sockets are created in blocking mode. However, note that the platform level socket is always non-blocking, and blocking mode is a GSocket level feature.

Since glibmm 2.22:
Parameters
blockingWhether to use blocking I/O or not.
void Gio::Socket::set_broadcast ( bool  broadcast)

Sets whether socket should allow sending to broadcast addresses.

This is false by default.

Since glibmm 2.32:
Parameters
broadcastWhether socket should allow sending to broadcast addresses.
void Gio::Socket::set_keepalive ( bool  keepalive)

Sets or unsets the SO_KEEPALIVE flag on the underlying socket.

When this flag is set on a socket, the system will attempt to verify that the remote socket endpoint is still present if a sufficiently long period of time passes with no data being exchanged. If the system is unable to verify the presence of the remote endpoint, it will automatically close the connection.

This option is only functional on certain kinds of sockets. (Notably, Gio::Socket::Protocol::TCP sockets.)

The exact time between pings is system- and protocol-dependent, but will normally be at least two hours. Most commonly, you would set this flag on a server socket if you want to allow clients to remain idle for long periods of time, but also want to ensure that connections are eventually garbage-collected if clients crash or become unreachable.

Since glibmm 2.22:
Parameters
keepaliveValue for the keepalive flag.
void Gio::Socket::set_listen_backlog ( int  backlog)

Sets the maximum number of outstanding connections allowed when listening on this socket.

If more clients than this are connecting to the socket and the application is not handling them on time then the new connections will be refused.

Note that this must be called before g_socket_listen() and has no effect if called after that.

Since glibmm 2.22:
Parameters
backlogThe maximum number of pending connections.
void Gio::Socket::set_multicast_loopback ( bool  loopback)

Sets whether outgoing multicast packets will be received by sockets listening on that multicast address on the same host.

This is true by default.

Since glibmm 2.32:
Parameters
loopbackWhether socket should receive messages sent to its multicast groups from the local host.
void Gio::Socket::set_multicast_ttl ( guint  ttl)

Sets the time-to-live for outgoing multicast datagrams on socket.

By default, this is 1, meaning that multicast packets will not leave the local network.

Since glibmm 2.32:
Parameters
ttlThe time-to-live value for all multicast datagrams on socket.
bool Gio::Socket::set_option ( int  level,
int  optname,
int  value 
)

Sets the value of an integer-valued option on socket, as with setsockopt().

(If you need to set a non-integer-valued option, you will need to call setsockopt() directly.)

The [<gio/gnetworking.h>][gio-gnetworking.h] header pulls in system headers that will define most of the standard/portable socket options. For unusual socket protocols or platform-dependent options, you may need to include additional headers.

Since glibmm 2.36:
Parameters
levelThe "API level" of the option (eg, SOL_SOCKET).
optnameThe "name" of the option (eg, SO_BROADCAST).
valueThe value to set the option to.
Returns
Success or failure. On failure, error will be set, and the system error value (errno or WSAGetLastError()) will still be set to the result of the setsockopt() call.
Exceptions
Glib::Error
void Gio::Socket::set_timeout ( guint  timeout)

Sets the time in seconds after which I/O operations on socket will time out if they have not yet completed.

On a blocking socket, this means that any blocking Socket operation will time out after timeout seconds of inactivity, returning Gio::Error::TIMED_OUT.

On a non-blocking socket, calls to g_socket_condition_wait() will also fail with Gio::Error::TIMED_OUT after the given time. Sources created with g_socket_create_source() will trigger after timeout seconds of inactivity, with the requested condition set, at which point calling g_socket_receive(), g_socket_send(), g_socket_check_connect_result(), etc, will fail with Gio::Error::TIMED_OUT.

If timeout is 0 (the default), operations will never time out on their own.

Note that if an I/O operation is interrupted by a signal, this may cause the timeout to be reset.

Since glibmm 2.26:
Parameters
timeoutThe timeout for socket, in seconds, or 0 for none.
void Gio::Socket::set_ttl ( guint  ttl)

Sets the time-to-live for outgoing unicast packets on socket.

By default the platform-specific default value is used.

Since glibmm 2.32:
Parameters
ttlThe time-to-live value for all unicast packets on socket.
void Gio::Socket::shutdown ( bool  shutdown_read,
bool  shutdown_write 
)

Shut down part or all of a full-duplex connection.

If shutdown_read is true then the receiving side of the connection is shut down, and further reading is disallowed.

If shutdown_write is true then the sending side of the connection is shut down, and further writing is disallowed.

It is allowed for both shutdown_read and shutdown_write to be true.

One example where it is useful to shut down only one side of a connection is graceful disconnect for TCP connections where you close the sending side, then wait for the other side to close the connection, thus ensuring that the other side saw all sent data.

Since glibmm 2.22:
Parameters
shutdown_readWhether to shut down the read side.
shutdown_writeWhether to shut down the write side.
Exceptions
Glib::Error
bool Gio::Socket::speaks_ipv4 ( ) const

Checks if a socket is capable of speaking IPv4.

IPv4 sockets are capable of speaking IPv4. On some operating systems and under some combinations of circumstances IPv6 sockets are also capable of speaking IPv4. See RFC 3493 section 3.7 for more information.

No other types of sockets are currently considered as being capable of speaking IPv4.

Since glibmm 2.22:
Returns
true if this socket can be used with IPv4.

Friends And Related Function Documentation

Glib::RefPtr< Gio::Socket > wrap ( GSocket *  object,
bool  take_copy = false 
)
related

A Glib::wrap() method for this object.

Parameters
objectThe C instance.
take_copyFalse if the result should take ownership of the C instance. True if it should take a new copy or ref.
Returns
A C++ instance that wraps this C instance.