Gio::SocketControlMessage Class Reference
Portable Network I/O Functionality

A Socket control message. More...

`#include <giomm/socketcontrolmessage.h>`

Inheritance diagram for Gio::SocketControlMessage:
[legend]

## Public Member Functions

| SocketControlMessage (SocketControlMessage&& src) noexcept
SocketControlMessage& | operator= (SocketControlMessage&& src) noexcept
| ~SocketControlMessage () noexcept override
GSocketControlMessage* | gobj ()
| Provides access to the underlying C GObject. More...
const GSocketControlMessage* | gobj () const
| Provides access to the underlying C GObject. More...
GSocketControlMessage* | gobj_copy ()
| Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...
int | get_level () const
| Returns the "level" (i.e. the originating protocol) of the control message. More...
int | get_msg_type () const
| Returns the protocol specific type of the control message. More...
gsize | get_size () const
| Returns the space required for the control message, not including headers or alignment. More...
void | serialize (gpointer data)
| Converts the data in the message to bytes placed in the message. More...
virtual gsize | get_size_vfunc () const
virtual int | get_level_vfunc () const
virtual int | get_type_vfunc () const
virtual void | serialize_vfunc (gpointer data)
Public Member Functions inherited from Glib::Object
| Object (const Object&)=delete
Object& | operator= (const Object&)=delete
| Object (Object&& src) noexcept
Object& | operator= (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
ObjectBase& | operator= (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...
void | 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...
void | 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...
sigc::connection | connect_property_changed_with_return (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_with_return (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)
| ~trackable ()
void | add_destroy_notify_callback (void *data, func_destroy_notify func) const
void | notify_callbacks ()
trackable & | operator= (const trackable &src)
trackable & | operator= (trackable &&src)
void | remove_destroy_notify_callback (void *data) 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< SocketControlMessage > | deserialize (int level, int type, gsize size, gpointer data)
| Tries to deserialize a socket control message of a given level and type. More...

## Protected Types

using | DeserializeFunc = Glib::RefPtr< SocketControlMessage >(*)(int level, int type, gsize size, gpointer data)
| Pointer to a function that can be called from deserialize() or g_socket_control_message_deserialize(). More...

## Protected Member Functions

| SocketControlMessage ()
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
ObjectBase& | operator= (ObjectBase&& src) noexcept
virtual | ~ObjectBase () noexcept=0
void | initialize (GObject* castitem)
void | initialize_move (GObject* castitem, Glib::ObjectBase* previous_wrapper)

## Static Protected Member Functions

static void | add_deserialize_func (DeserializeFunc func)
| Register a deserialize function. More...

## Related Functions

(Note that these are not member functions.)
Glib::RefPtr< Gio::SocketControlMessage > | wrap (GSocketControlMessage* object, bool take_copy=false)
| A Glib::wrap() method for this object. More...
Related Functions inherited from Glib::Object
Glib::RefPtr< Glib::Object > | wrap (GObject* object, bool take_copy=false)

## Additional Inherited Members

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

## Detailed Description

A Socket control message.

A SocketControlMessage is a special-purpose utility message that can be sent to or received from a Socket. These types of messages are often called "ancillary data".

The message can represent some sort of special instruction to or information from the socket or can represent a special kind of transfer to the peer (for example, sending a file description over a UNIX socket).

These messages are sent with Gio::Socket::send() and received with Gio::Socket::receive().

To extend the set of control message that can be sent, subclass this class and override the get_size_vfunc(), get_level_vfunc(), get_type_vfunc() and serialize_vfunc() methods.

To extend the set of control messages that can be received, subclass this class and implement a DeserializeFunc function. Typically it would be a static class method. Also, make sure you register the DeserializeFunc function with a call to add_deserialize_func() before calling Gio::Socket::receive() to read such a message.

Since glibmm 2.28:

## Member Typedef Documentation

using Gio::SocketControlMessage::DeserializeFunc = Glib::RefPtr<SocketControlMessage> (*) (int level, int type, gsize size, gpointer data)

protected

Pointer to a function that can be called from deserialize() or g_socket_control_message_deserialize().

For instance,

Glib::RefPtr<SocketControlMessage> my_deserialize_func(
int level, int type, gsize size, gpointer data);

Parameters

  level | A socket level.
  type | A socket control message type for the given level.
  size | The size of the data in bytes.
  data | Pointer to the message data (element-type guint8).

Returns
  The deserialized message or an empty Glib::RefPtr. The returned message can be a subclass of SocketControlMessage.

## Constructor & Destructor Documentation

Gio::SocketControlMessage::SocketControlMessage | ( | SocketControlMessage&& | src | ) |

noexcept

Gio::SocketControlMessage::~SocketControlMessage | ( |  | ) |

override noexcept

Gio::SocketControlMessage::SocketControlMessage | ( |  | ) |

protected

## Member Function Documentation

static void Gio::SocketControlMessage::add_deserialize_func | ( | DeserializeFunc | func | ) |

static protected

Register a deserialize function.

If the same function is registered multiple times, only the first registration has an effect.

In GLib, deserialize() is a class virtual function (not associated with an instance). Such functions don't exist in C++. A function registered with add_deserialize_func() is a kind of replacement.

static Glib::RefPtr<SocketControlMessage> Gio::SocketControlMessage::deserialize | ( | int | level,
|  | int | type,
|  | gsize | size,
|  | gpointer | data
| ) |  |

static

Tries to deserialize a socket control message of a given level and type.

This will ask all known (to GType) subclasses of SocketControlMessage if they can understand this kind of message and if so deserialize it into a SocketControlMessage.

If there is no implementation for this kind of control message, `nullptr` will be returned.

Since glibmm 2.22:

Parameters

  level | A socket level.
  type | A socket control message type for the given level.
  size | The size of the data in bytes.
  data | Pointer to the message data.

Returns
  The deserialized message or `nullptr`.

int Gio::SocketControlMessage::get_level | ( |  | ) | const

Returns the "level" (i.e. the originating protocol) of the control message.

This is often SOL_SOCKET.

Since glibmm 2.22:

Returns
  An integer describing the level.

virtual int Gio::SocketControlMessage::get_level_vfunc | ( |  | ) | const

virtual

int Gio::SocketControlMessage::get_msg_type | ( |  | ) | const

Returns the protocol specific type of the control message.

For instance, for UNIX fd passing this would be SCM_RIGHTS.

Since glibmm 2.22:

Returns
  An integer describing the type of control message.

gsize Gio::SocketControlMessage::get_size | ( |  | ) | const

Returns the space required for the control message, not including headers or alignment.

Since glibmm 2.22:

Returns
  The number of bytes required.

virtual gsize Gio::SocketControlMessage::get_size_vfunc | ( |  | ) | const

virtual

static GType Gio::SocketControlMessage::get_type | ( |  | ) |

static

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

virtual int Gio::SocketControlMessage::get_type_vfunc | ( |  | ) | const

virtual

GSocketControlMessage* Gio::SocketControlMessage::gobj | ( |  | ) |

inline

Provides access to the underlying C GObject.

const GSocketControlMessage* Gio::SocketControlMessage::gobj | ( |  | ) | const

inline

Provides access to the underlying C GObject.

GSocketControlMessage* Gio::SocketControlMessage::gobj_copy | ( |  | ) |

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

SocketControlMessage& Gio::SocketControlMessage::operator= | ( | SocketControlMessage&& | src | ) |

noexcept

void Gio::SocketControlMessage::serialize | ( | gpointer | data | ) |

Converts the data in the message to bytes placed in the message.

data is guaranteed to have enough space to fit the size returned by g_socket_control_message_get_size() on this object.

Since glibmm 2.22:

Parameters

  data | A buffer to write data to.

virtual void Gio::SocketControlMessage::serialize_vfunc | ( | gpointer | data | ) |

virtual

## Friends And Related Function Documentation

Glib::RefPtr< Gio::SocketControlMessage > wrap | ( | GSocketControlMessage * | object,
|  | bool | take_copy = `false`
| ) |  |

related

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

Parameters

  object | The C instance.
  take_copy | False 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.