glibmm: Gio::Seekable Class Reference

glibmm 2.86.0

Public Member Functions | Static Public Member Functions | Protected Member Functions | Related Symbols | List of all members
Gio::Seekable Class Reference
Stream Classes

Stream seeking interface. More...

`#include <giomm/seekable.h>`

Inheritance diagram for Gio::Seekable:
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## Public Member Functions
| Seekable (Seekable && src) noexcept
Seekable & | operator= (Seekable && src) noexcept
| ~Seekable () noexcept override
GSeekable * | gobj ()
| Provides access to the underlying C GObject.
const GSeekable * | gobj () const
| Provides access to the underlying C GObject.
goffset | tell () const
| Tells the current position within the stream.
bool | can_seek () const
| Tests if the stream supports the SeekableIface.
bool | seek (goffset offset, Glib::SeekType type, const Glib::RefPtr< Cancellable > & cancellable)
| Seeks in the stream by the given offset, modified by type.
bool | seek (goffset offset, Glib::SeekType type)
| A seek() convenience overload.
bool | can_truncate () const
| Tests if the length of the stream can be adjusted with g_seekable_truncate().
bool | truncate (goffset offset, const Glib::RefPtr< Cancellable > & cancellable)
| Truncates a stream with a given #offset.
bool | truncate (goffset offset)
| A truncate() convenience overload.
Public Member Functions inherited from Glib::Interface
| Interface ()
| A Default constructor.
| Interface (Interface && src) noexcept
Interface & | operator= (Interface && src) noexcept
| Interface (const Glib::Interface_Class & interface_class)
| Called by constructors of derived classes.
| Interface (GObject * castitem)
| Called by constructors of derived classes.
| ~Interface () noexcept override
| Interface (const Interface &)=delete
Interface & | operator= (const Interface &)=delete
GObject * | gobj ()
const GObject * | gobj () const
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.
void | get_property_value (const Glib::ustring & property_name, Glib::ValueBase & value) const
| You probably want to use a specific property_*() accessor method instead.
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.
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.
template<class PropertyType>
PropertyType | get_property (const Glib::ustring & property_name) const
| You probably want to use a specific property_*() accessor method instead.
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.
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.
void | freeze_notify ()
| Increases the freeze count on object.
void | thaw_notify ()
| Reverts the effect of a previous call to freeze_notify().
virtual void | reference () const
| Increment the reference count for this object.
virtual void | unreference () const
| Decrement the reference count for this object.
GObject * | gobj ()
| Provides access to the underlying C GObject.
const GObject * | gobj () const
| Provides access to the underlying C GObject.
GObject * | gobj_copy () const
| Give a ref-ed copy to someone. Use for direct struct access.

## Static Public Member Functions
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.

## Protected Member Functions
| Seekable ()
| You should derive from this class to use it.
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.
| ObjectBase (const char * custom_type_name)
| A derived constructor always overrides this choice.
| 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.
| 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)

## Related Symbols
(Note that these are not member symbols.)
Glib::RefPtr< Gio::Seekable > | wrap (GSeekable * object, bool take_copy=false)
| A Glib::wrap() method for this object.

## Detailed Description

Stream seeking interface.

Seekable is implemented by streams (implementations of InputStream or OutputStream) that support seeking. To find the position of a stream, use tell(). To find out if a stream supports seeking, use can_seek(). To position a stream, use seek(). To find out if a stream supports truncating, use can_truncate(). To truncate a stream, use truncate().

Since glibmm 2.16

## Constructor & Destructor Documentation

## ◆ Seekable() [1/2]

Gio::Seekable::Seekable | ( |  | ) |
| protected

You should derive from this class to use it.

## ◆ Seekable() [2/2]

Gio::Seekable::Seekable | ( | Seekable && | src | ) |
| noexcept

## ◆ ~Seekable()

Gio::Seekable::~Seekable | ( |  | ) |
| overridenoexcept

## Member Function Documentation

## ◆ add_interface()

void Gio::Seekable::add_interface | ( | GType | gtype_implementer | ) |
| static

## ◆ can_seek()

bool Gio::Seekable::can_seek | ( |  | ) | const

Tests if the stream supports the SeekableIface.

Returns
  true if seekable can be seeked. false otherwise.

## ◆ can_truncate()

bool Gio::Seekable::can_truncate | ( |  | ) | const

Tests if the length of the stream can be adjusted with g_seekable_truncate().

Returns
  true if the stream can be truncated, false otherwise.

## ◆ get_type()

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

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

## ◆ gobj() [1/2]

GSeekable * Gio::Seekable::gobj | ( |  | ) |
| inline

Provides access to the underlying C GObject.

## ◆ gobj() [2/2]

const GSeekable * Gio::Seekable::gobj | ( |  | ) | const
| inline

Provides access to the underlying C GObject.

## ◆ operator=()

Seekable & Gio::Seekable::operator= | ( | Seekable && | src | ) |
| noexcept

## ◆ seek() [1/2]

bool Gio::Seekable::seek | ( | goffset | offset,
|  | Glib::SeekType | type )

A seek() convenience overload.

## ◆ seek() [2/2]

bool Gio::Seekable::seek | ( | goffset | offset,
|  | Glib::SeekType | type,
|  | const Glib::RefPtr< Cancellable > & | cancellable )

Seeks in the stream by the given offset, modified by type.

The operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, a Gio::Error will be thrown with CANCELLED.

Parameters

  offset | A #goffset.
  type | A SeekType.
  cancellable | Cancellable object.

Returns
  true if successful. If an error has occurred, this function will return false and set error appropriately if present.

Exceptions

  Glib::Error |

## ◆ tell()

goffset Gio::Seekable::tell | ( |  | ) | const

Tells the current position within the stream.

Returns
  The (positive or zero) offset from the beginning of the buffer, zero if the target is not seekable.

## ◆ truncate() [1/2]

bool Gio::Seekable::truncate | ( | goffset | offset | ) |

A truncate() convenience overload.

## ◆ truncate() [2/2]

bool Gio::Seekable::truncate | ( | goffset | offset,
|  | const Glib::RefPtr< Cancellable > & | cancellable )

Truncates a stream with a given #offset.

The operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, a Gio::Error will be thrown with CANCELLED. If an operation was partially finished when the operation was cancelled the partial result will be returned, without an error.

Parameters

  offset | A #goffset.
  cancellable | Cancellable object.

Returns
  true if successful. If an error has occurred, this function will return false and set error appropriately if present.

Exceptions

  Glib::Error |

## Friends And Related Symbol Documentation

## ◆ wrap()

Glib::RefPtr< Gio::Seekable > wrap | ( | GSeekable * | 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.