glibmm: Gio::InputStream Class Reference

Base class for implementing streaming input. More...

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

Inheritance diagram for Gio::InputStream:

Public Member Functions

 InputStream (InputStream&& src) noexcept
 
InputStreamoperator= (InputStream&& src) noexcept
 
 ~InputStream () noexcept override
 
GInputStream* gobj ()
 Provides access to the underlying C GObject. More...

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

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

 
gssize read (void* buffer, gsize count, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to read count bytes from the stream into the buffer starting at buffer. More...

 
gssize read (void* buffer, gsize count)
 A read() convenience overload. More...

 
bool read_all (void* buffer, gsize count, gsize& bytes_read, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to read count bytes from the stream into the buffer starting at buffer. More...

 
bool read_all (void* buffer, gsize count, gsize& bytes_read)
 A read_all() convenience overload. More...

 
Glib::RefPtr< Glib::Bytesread_bytes (gsize count, const Glib::RefPtr< Cancellable >& cancellable)
 Like g_input_stream_read(), this tries to read count bytes from the stream in a blocking fashion. More...

 
void read_bytes_async (gsize count, const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous read of count bytes from the stream into a new Glib::Bytes. More...

 
void read_bytes_async (gsize count, const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous read of count bytes from the stream into a new Glib::Bytes. More...

 
Glib::RefPtr< Glib::Bytesread_bytes_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes an asynchronous stream read-into-Bytes operation. More...

 
gssize skip (gsize count, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to skip count bytes from the stream. More...

 
gssize skip (gsize count)
 A skip() convenience overload. More...

 
bool close (const Glib::RefPtr< Cancellable >& cancellable)
 Closes the stream, releasing resources related to it. More...

 
bool close ()
 A close() convenience overload. More...

 
void read_async (void* buffer, gsize count, const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous read of count bytes from the stream into the buffer starting at buffer. More...

 
void read_async (void* buffer, gsize count, const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous read of count bytes from the stream into the buffer starting at buffer. More...

 
gssize read_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes an asynchronous stream read operation. More...

 
void read_all_async (void* buffer, gsize count, const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous read of count bytes from the stream into the buffer starting at buffer. More...

 
void read_all_async (void* buffer, gsize count, const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous read of count bytes from the stream into the buffer starting at buffer. More...

 
bool read_all_finish (const Glib::RefPtr< AsyncResult >& result, gsize& bytes_read)
 Finishes an asynchronous stream read operation started with g_input_stream_read_all_async(). More...

 
void skip_async (gsize count, const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous skip of count bytes from the stream into the buffer starting at buffer. More...

 
void skip_async (gsize count, const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous skip of count bytes from the stream into the buffer starting at buffer. More...

 
gssize skip_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes a stream skip operation. More...

 
void close_async (const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Requests an asynchronous closes of the stream, releasing resources related to it. More...

 
void close_async (const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Requests an asynchronous closes of the stream, releasing resources related to it. More...

 
gboolean close_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes closing a stream asynchronously, started from g_input_stream_close_async(). More...

 
bool is_closed () const
 Checks if an input stream is closed. More...

 
bool has_pending () const
 Checks if an input stream has pending actions. 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
 

Static Public Member Functions

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

 

Protected Member Functions

 InputStream ()
 
bool set_pending ()
 Sets stream to have actions pending. More...

 
void clear_pending ()
 Clears the pending flag on stream. More...

 
virtual gssize read_vfunc (void* buffer, gsize count, const Glib::RefPtr< Cancellable >& cancellable)
 
virtual gssize skip_vfunc (gsize count, const Glib::RefPtr< Cancellable >& cancellable)
 
virtual bool close_vfunc (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)
 

Related Functions

(Note that these are not member functions.)

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

 

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
 
- Public Types inherited from sigc::notifiable
typedef internal::func_destroy_notify func_destroy_notify
 

Detailed Description

Base class for implementing streaming input.

Since glibmm 2.16:

Constructor & Destructor Documentation

Gio::InputStream::InputStream ( InputStream&&  src)
noexcept
Gio::InputStream::~InputStream ( )
overridenoexcept
Gio::InputStream::InputStream ( )
protected

Member Function Documentation

void Gio::InputStream::clear_pending ( )
protected

Clears the pending flag on stream.

Since glibmm 2.50:
bool Gio::InputStream::close ( const Glib::RefPtr< Cancellable >&  cancellable)

Closes the stream, releasing resources related to it.

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

Streams 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.

Some streams might keep the backing store of the stream (e.g. a file descriptor) open after the stream is closed. See the documentation for the individual stream for details.

On failure the first error that happened will be reported, but the close operation will finish as much as possible. A stream that failed to close will still throw a Gio::Error with CLOSED for all operations. Still, it is important to check and report the error to the user.

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. Cancelling a close will still leave the stream closed, but some streams can use a faster close that doesn't block to e.g. check errors.

Parameters
cancellableCancellable object.
Returns
true on success, false on failure.
Exceptions
Glib::Error
bool Gio::InputStream::close ( )

A close() convenience overload.

void Gio::InputStream::close_async ( const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Requests an asynchronous closes of the stream, releasing resources related to it.

When the operation is finished slot will be called. You can then call close_finish() to get the result of the operation.

For behaviour details see close().

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
slotCallback to call when the request is satisfied.
cancellableA Cancellable object.
io_priorityThe I/O priority of the request.
void Gio::InputStream::close_async ( const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Requests an asynchronous closes of the stream, releasing resources related to it.

When the operation is finished slot will be called. You can then call close_finish() to get the result of the operation.

For behaviour details see close().

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
slotCallback to call when the request is satisfied.
io_priorityThe I/O priority of the request.
gboolean Gio::InputStream::close_finish ( const Glib::RefPtr< AsyncResult >&  result)

Finishes closing a stream asynchronously, started from g_input_stream_close_async().

Parameters
resultA AsyncResult.
Returns
true if the stream was closed successfully.
Exceptions
Glib::Error
virtual bool Gio::InputStream::close_vfunc ( const Glib::RefPtr< Cancellable >&  cancellable)
protectedvirtual
Exceptions
Glib::Error.
static GType Gio::InputStream::get_type ( )
static

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

GInputStream* Gio::InputStream::gobj ( )
inline

Provides access to the underlying C GObject.

const GInputStream* Gio::InputStream::gobj ( ) const
inline

Provides access to the underlying C GObject.

GInputStream* Gio::InputStream::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::InputStream::has_pending ( ) const

Checks if an input stream has pending actions.

Since glibmm 2.50:
Returns
true if stream has pending actions.
bool Gio::InputStream::is_closed ( ) const

Checks if an input stream is closed.

Since glibmm 2.50:
Returns
true if the stream is closed.
InputStream& Gio::InputStream::operator= ( InputStream&&  src)
noexcept
gssize Gio::InputStream::read ( void *  buffer,
gsize  count,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to read count bytes from the stream into the buffer starting at buffer.

Will block during this read.

If count is zero returns zero and does nothing. A value of count larger than G_MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes read into the buffer is returned. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file. Zero is returned on end of file (or if count is zero), but never otherwise.

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
bufferA buffer to read data into (which should be at least count bytes long).
countThe number of bytes that will be read from the stream.
cancellableCancellable object.
Returns
Number of bytes read, or -1 on error.
Exceptions
Glib::Error
gssize Gio::InputStream::read ( void *  buffer,
gsize  count 
)

A read() convenience overload.

bool Gio::InputStream::read_all ( void *  buffer,
gsize  count,
gsize &  bytes_read,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to read count bytes from the stream into the buffer starting at buffer.

Will block during this read.

This function is similar to g_input_stream_read(), except it tries to read as many bytes as requested, only stopping on an error or end of stream.

On a successful read of count bytes, or if we reached the end of the stream, true is returned, and bytes_read is set to the number of bytes read into buffer.

If there is an error during the operation false is returned and error is set to indicate the error status.

As a special exception to the normal conventions for functions that use Error, if this function returns false (and sets error) then bytes_read will be set to the number of bytes that were successfully read before the error was encountered. This functionality is only available from C. If you need it from another language then you must write your own loop around g_input_stream_read().

Parameters
bufferA buffer to read data into (which should be at least count bytes long).
countThe number of bytes that will be read from the stream.
bytes_readLocation to store the number of bytes that was read from the stream.
cancellableOptional Cancellable object, nullptr to ignore.
Returns
true on success, false if there was an error.
Exceptions
Glib::Error
bool Gio::InputStream::read_all ( void *  buffer,
gsize  count,
gsize &  bytes_read 
)

A read_all() convenience overload.

void Gio::InputStream::read_all_async ( void *  buffer,
gsize  count,
const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous read of count bytes from the stream into the buffer starting at buffer.

This is the asynchronous equivalent of read_all().

When the operation is finished slot will be called. You can then call read_all_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes read into the buffer will be passed to the slot callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is PRIORITY_DEFAULT.

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
bufferA buffer to read data into (which should be at least count bytes long).
countThe number of bytes that will be read from the stream.
slotCallback to call when the request is satisfied.
cancellableA Cancellable object.
io_priorityThe I/O priority of the request.
void Gio::InputStream::read_all_async ( void *  buffer,
gsize  count,
const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous read of count bytes from the stream into the buffer starting at buffer.

This is the asynchronous equivalent of read_all().

When the operation is finished slot will be called. You can then call read_all_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in a Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes read into the buffer will be passed to the slot callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is PRIORITY_DEFAULT.

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
bufferA buffer to read data into (which should be at least count bytes long).
countThe number of bytes that will be read from the stream.
slotCallback to call when the request is satisfied.
io_priorityThe I/O priority of the request.
bool Gio::InputStream::read_all_finish ( const Glib::RefPtr< AsyncResult >&  result,
gsize &  bytes_read 
)

Finishes an asynchronous stream read operation started with g_input_stream_read_all_async().

As a special exception to the normal conventions for functions that use Error, if this function returns false (and sets error) then bytes_read will be set to the number of bytes that were successfully read before the error was encountered. This functionality is only available from C. If you need it from another language then you must write your own loop around g_input_stream_read_async().

Since glibmm 2.44:
Parameters
resultA AsyncResult.
bytes_readLocation to store the number of bytes that was read from the stream.
Returns
true on success, false if there was an error.
Exceptions
Glib::Error
void Gio::InputStream::read_async ( void *  buffer,
gsize  count,
const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous read of count bytes from the stream into the buffer starting at buffer.

When the operation is finished slot will be called. You can then call read_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes read into the buffer will be passed to the slot callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is PRIORITY_DEFAULT.

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
bufferA buffer to read data into (which should be at least count bytes long).
countThe number of bytes that will be read from the stream.
slotCallback to call when the request is satisfied.
cancellableA Cancellable object.
io_priorityThe I/O priority of the request.
void Gio::InputStream::read_async ( void *  buffer,
gsize  count,
const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous read of count bytes from the stream into the buffer starting at buffer.

When the operation is finished slot will be called. You can then call read_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in a Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes read into the buffer will be passed to the slot callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is PRIORITY_DEFAULT.

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
bufferA buffer to read data into (which should be at least count bytes long).
countThe number of bytes that will be read from the stream.
slotCallback to call when the request is satisfied.
io_priorityThe I/O priority of the request.
Glib::RefPtr<Glib::Bytes> Gio::InputStream::read_bytes ( gsize  count,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Like g_input_stream_read(), this tries to read count bytes from the stream in a blocking fashion.

However, rather than reading into a user-supplied buffer, this will create a new Bytes containing the data that was read. This may be easier to use from language bindings.

If count is zero, returns a zero-length Bytes and does nothing. A value of count larger than G_MAXSSIZE will cause a Gio::Error::INVALID_ARGUMENT error.

On success, a new Bytes is returned. It is not an error if the size of this object is not the same as the requested size, as it can happen e.g. near the end of a file. A zero-length Bytes is returned on end of file (or if count is zero), but never otherwise.

If cancellable is not nullptr, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error Gio::Error::CANCELLED will be returned. If an operation was partially finished when the operation was cancelled the partial result will be returned, without an error.

On error nullptr is returned and error is set accordingly.

Since glibmm 2.34:
Parameters
countMaximum number of bytes that will be read from the stream. Common values include 4096 and 8192.
cancellableOptional Cancellable object, nullptr to ignore.
Returns
A new Bytes, or nullptr on error.
Exceptions
Glib::Error
void Gio::InputStream::read_bytes_async ( gsize  count,
const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous read of count bytes from the stream into a new Glib::Bytes.

When the operation is finished slot will be called. You can then call read_bytes_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the new Glib::Bytes will be passed to the callback. It is not an error if this is smaller than the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding I/O request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. The default priority is PRIORITY_DEFAULT.

Parameters
countThe number of bytes that will be read from the stream.
slotCallback to call when the request is satisfied.
cancellableA Cancellable object.
io_priorityThe I/O priority of the request.
Since glibmm 2.34:
void Gio::InputStream::read_bytes_async ( gsize  count,
const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous read of count bytes from the stream into a new Glib::Bytes.

When the operation is finished slot will be called. You can then call read_bytes_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the new Glib::Bytes will be passed to the callback. It is not an error if this is smaller than the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding I/O request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. The default priority is PRIORITY_DEFAULT.

Parameters
countThe number of bytes that will be read from the stream.
slotCallback to call when the request is satisfied.h
io_priorityThe I/O priority of the request.
Since glibmm 2.34:
Glib::RefPtr<Glib::Bytes> Gio::InputStream::read_bytes_finish ( const Glib::RefPtr< AsyncResult >&  result)

Finishes an asynchronous stream read-into-Bytes operation.

Since glibmm 2.34:
Parameters
resultA AsyncResult.
Returns
The newly-allocated Bytes, or nullptr on error.
Exceptions
Glib::Error
gssize Gio::InputStream::read_finish ( const Glib::RefPtr< AsyncResult >&  result)

Finishes an asynchronous stream read operation.

Parameters
resultA AsyncResult.
Returns
Number of bytes read in, or -1 on error, or 0 on end of file.
Exceptions
Glib::Error
virtual gssize Gio::InputStream::read_vfunc ( void *  buffer,
gsize  count,
const Glib::RefPtr< Cancellable >&  cancellable 
)
protectedvirtual
Exceptions
Glib::Error.
bool Gio::InputStream::set_pending ( )
protected

Sets stream to have actions pending.

If the pending flag is already set or stream is closed, it will return false and set error.

Since glibmm 2.50:
Returns
true if pending was previously unset and is now set.
Exceptions
Glib::Error
gssize Gio::InputStream::skip ( gsize  count,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to skip count bytes from the stream.

Will block during the operation.

This is identical to g_input_stream_read(), from a behaviour standpoint, but the bytes that are skipped are not returned to the user. Some streams have an implementation that is more efficient than reading the data.

This function is optional for inherited classes, as the default implementation emulates it using read.

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
countThe number of bytes that will be skipped from the stream.
cancellableCancellable object.
Returns
Number of bytes skipped, or -1 on error.
Exceptions
Glib::Error
gssize Gio::InputStream::skip ( gsize  count)

A skip() convenience overload.

void Gio::InputStream::skip_async ( gsize  count,
const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous skip of count bytes from the stream into the buffer starting at buffer.

When the operation is finished slot will be called. You can then call skip_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes skipped will be passed to the callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to skip as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is PRIORITY_DEFAULT.

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
countThe number of bytes that will be skipped from the stream.
slotCallback to call when the request is satisfied.
cancellableA Cancellable object.
io_priorityThe I/O priority of the request.
void Gio::InputStream::skip_async ( gsize  count,
const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous skip of count bytes from the stream into the buffer starting at buffer.

When the operation is finished slot will be called. You can then call skip_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in Gio::Error with PENDING being thrown.

A value of count larger than MAXSSIZE will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes skipped will be passed to the callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to skip as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is PRIORITY_DEFAULT.

The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

Parameters
countThe number of bytes that will be skipped from the stream.
slotCallback to call when the request is satisfied.
io_priorityThe I/O priority of the request.
gssize Gio::InputStream::skip_finish ( const Glib::RefPtr< AsyncResult >&  result)

Finishes a stream skip operation.

Parameters
resultA AsyncResult.
Returns
The size of the bytes skipped, or %-1 on error.
Exceptions
Glib::Error
virtual gssize Gio::InputStream::skip_vfunc ( gsize  count,
const Glib::RefPtr< Cancellable >&  cancellable 
)
protectedvirtual
Exceptions
Glib::Error.

Friends And Related Function Documentation

Glib::RefPtr< Gio::InputStream > wrap ( GInputStream *  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.