Gio::OutputStream Class Reference
[Stream Classes]

Base class for implementing streaming output. More...

#include <giomm/outputstream.h>

Inheritance diagram for Gio::OutputStream:
Inheritance graph
[legend]

List of all members.

Public Member Functions

virtual ~OutputStream ()
GOutputStream* gobj ()
 Provides access to the underlying C GObject.
const GOutputStream* gobj () const
 Provides access to the underlying C GObject.
GOutputStream* gobj_copy ()
 Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.
gssize write (const void* buffer, gsize count, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to write count bytes from buffer into the stream.
gssize write (const void* buffer, gsize count)
 Tries to write count bytes from buffer into the stream.
gssize write (const std::string& buffer, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to write count bytes from buffer into the stream.
gssize write (const std::string& buffer)
 Tries to write count bytes from buffer into the stream.
bool write_all (const void* buffer, gsize count, gsize& bytes_written, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to write count bytes from buffer into the stream.
bool write_all (const void* buffer, gsize count, gsize& bytes_written)
 Tries to write count bytes from buffer into the stream.
bool write_all (const std::string& buffer, gsize& bytes_written, const Glib::RefPtr< Cancellable >& cancellable)
 Tries to write count bytes from buffer into the stream.
bool write_all (const std::string& buffer, gsize& bytes_written)
 Tries to write count bytes from buffer into the stream.
gssize splice (const Glib::RefPtr< InputStream >& source, const Glib::RefPtr< Cancellable >& cancellable, OutputStreamSpliceFlags flags=OUTPUT_STREAM_SPLICE_NONE)
 Splices an input stream into an output stream.
gssize splice (const Glib::RefPtr< InputStream >& source, OutputStreamSpliceFlags flags=OUTPUT_STREAM_SPLICE_NONE)
 Splices an input stream into an output stream.
bool flush (const Glib::RefPtr< Cancellable >& cancellable)
 Flushed any outstanding buffers in the stream.
bool flush ()
 Flushed any outstanding buffers in the stream.
bool close (const Glib::RefPtr< Cancellable >& cancellable)
 Closes the stream, releasing resources related to it.
bool close ()
 Closes the stream, releasing resources related to it.
void write_async (const void* buffer, gsize count, const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous write of count bytes from buffer into the stream.
void write_async (const void* buffer, gsize count, const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Request an asynchronous write of count bytes from buffer into the stream.
gssize write_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes a stream write operation.
void splice_async (const Glib::RefPtr< InputStream >& source, const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, OutputStreamSpliceFlags flags=OUTPUT_STREAM_SPLICE_NONE, int io_priority=Glib::PRIORITY_DEFAULT)
 Splices a stream asynchronously.
void splice_async (const Glib::RefPtr< InputStream >& source, const SlotAsyncReady& slot, OutputStreamSpliceFlags flags=OUTPUT_STREAM_SPLICE_NONE, int io_priority=Glib::PRIORITY_DEFAULT)
 Splices a stream asynchronously.
gssize splice_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes an asynchronous stream splice operation.
void flush_async (const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Flushes a stream asynchronously.
void flush_async (const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Flushes a stream asynchronously.
bool flush_finish (const Glib::RefPtr< AsyncResult >& result)
 Finishes flushing an output stream.
void close_async (const SlotAsyncReady& slot, const Glib::RefPtr< Cancellable >& cancellable, int io_priority=Glib::PRIORITY_DEFAULT)
 Requests an asynchronous close of the stream, releasing resources related to it.
void close_async (const SlotAsyncReady& slot, int io_priority=Glib::PRIORITY_DEFAULT)
 Requests an asynchronous close of the stream, releasing resources related to it.
bool close_finish (const Glib::RefPtr< AsyncResult >& result)
 Closes an output stream.

Related Functions

(Note that these are not member functions.)



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

Detailed Description

Base class for implementing streaming output.

Since glibmm 2.16:

Constructor & Destructor Documentation

virtual Gio::OutputStream::~OutputStream (  )  [virtual]

Member Function Documentation

bool Gio::OutputStream::close (  ) 

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.

Closing a stream will automatically flush any outstanding buffers in the stream.

Streams will be automatically closed when the last reference is dropped, but you might want to call 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, otherwise there might be a loss of data as all data might not be written.

The operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, a Gio::Error with CANCELLED will be thrown. Cancelling a close will still leave the stream closed, but there some streams can use a faster close that doesn't block to e.g. check errors. On cancellation (as with any error) there is no guarantee that all written data will reach the target.

Parameters:
cancellable Optional cancellable object.
Returns:
true on success, false on failure.
bool Gio::OutputStream::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 cause an error to be thrown.

Closing a stream will automatically flush any outstanding buffers in the stream.

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, otherwise there might be a loss of data as all data might not be written.

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 there some streams can use a faster close that doesn't block to e.g. check errors. On cancellation (as with any error) there is no guarantee that all written data will reach the target.

Parameters:
cancellable Cancellable object.
Returns:
true on success, false on failure.
void Gio::OutputStream::close_async ( const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

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

When the operation is finished the slot will be called, giving the results. 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:
slot Callback slot to call when the request is satisfied.
io_priority The io priority of the request.
void Gio::OutputStream::close_async ( const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

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

When the operation is finished the slot will be called, giving the results. 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:
slot Callback slot to call when the request is satisfied.
cancellable Cancellable object.
io_priority The io priority of the request.
bool Gio::OutputStream::close_finish ( const Glib::RefPtr< AsyncResult >&  result  ) 

Closes an output stream.

Parameters:
result A AsyncResult.
Returns:
true if stream was successfully closed, false otherwise.
bool Gio::OutputStream::flush (  ) 

Flushed any outstanding buffers in the stream.

Will block during the operation. Closing the stream will implicitly cause a flush.

This function is optional for inherited classes.

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

Parameters:
cancellable Optional cancellable object.
Returns:
true on success, false on error.
bool Gio::OutputStream::flush ( const Glib::RefPtr< Cancellable >&  cancellable  ) 

Flushed any outstanding buffers in the stream.

Will block during the operation. Closing the stream will implicitly cause a flush.

This function is optional for inherited classes.

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:
cancellable Cancellable object.
Returns:
true on success, false on error.
void Gio::OutputStream::flush_async ( const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Flushes a stream asynchronously.

When the operation is finished the slot will be called, giving the results. You can then call flush_finish() to get the result of the operation. For behaviour details see flush().

Parameters:
slot Callback slot to call when the request is satisfied.
io_priority The io priority of the request.
void Gio::OutputStream::flush_async ( const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Flushes a stream asynchronously.

When the operation is finished the slot will be called, giving the results. You can then call flush_finish() to get the result of the operation. For behaviour details see flush().

Parameters:
slot Callback slot to call when the request is satisfied.
cancellable Cancellable object.
io_priority The io priority of the request.
bool Gio::OutputStream::flush_finish ( const Glib::RefPtr< AsyncResult >&  result  ) 

Finishes flushing an output stream.

Parameters:
result A GAsyncResult.
Returns:
true if flush operation suceeded, false otherwise.
const GOutputStream* Gio::OutputStream::gobj (  )  const [inline]

Provides access to the underlying C GObject.

Reimplemented from Glib::ObjectBase.

Reimplemented in Gio::BufferedOutputStream, Gio::DataOutputStream, Gio::FileOutputStream, Gio::FilterOutputStream, Gio::MemoryOutputStream, and Gio::UnixOutputStream.

GOutputStream* Gio::OutputStream::gobj (  )  [inline]

Provides access to the underlying C GObject.

Reimplemented from Glib::ObjectBase.

Reimplemented in Gio::BufferedOutputStream, Gio::DataOutputStream, Gio::FileOutputStream, Gio::FilterOutputStream, Gio::MemoryOutputStream, and Gio::UnixOutputStream.

GOutputStream* Gio::OutputStream::gobj_copy (  ) 

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

Reimplemented in Gio::BufferedOutputStream, Gio::DataOutputStream, Gio::FileOutputStream, Gio::FilterOutputStream, Gio::MemoryOutputStream, and Gio::UnixOutputStream.

gssize Gio::OutputStream::splice ( const Glib::RefPtr< InputStream >&  source,
OutputStreamSpliceFlags  flags = OUTPUT_STREAM_SPLICE_NONE 
)

Splices an input stream into an output stream.

Parameters:
source An InputStream.
flags A set of OutputStreamSpliceFlags. ignore.
Returns:
A gssize containing the size of the data spliced.
gssize Gio::OutputStream::splice ( const Glib::RefPtr< InputStream >&  source,
const Glib::RefPtr< Cancellable >&  cancellable,
OutputStreamSpliceFlags  flags = OUTPUT_STREAM_SPLICE_NONE 
)

Splices an input stream into an output stream.

Parameters:
source An InputStream.
flags A set of OutputStreamSpliceFlags.
cancellable A Cancellable object. ignore.
Returns:
A gssize containing the size of the data spliced.
void Gio::OutputStream::splice_async ( const Glib::RefPtr< InputStream >&  source,
const SlotAsyncReady slot,
OutputStreamSpliceFlags  flags = OUTPUT_STREAM_SPLICE_NONE,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Splices a stream asynchronously.

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

For the synchronous, blocking version of this function, see splice().

Parameters:
source An InputStream.
slot Callback slot to call when the request is satisfied.
io_priority The io priority of the request.
void Gio::OutputStream::splice_async ( const Glib::RefPtr< InputStream >&  source,
const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
OutputStreamSpliceFlags  flags = OUTPUT_STREAM_SPLICE_NONE,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Splices a stream asynchronously.

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

For the synchronous, blocking version of this function, see splice().

Parameters:
source An InputStream.
slot Callback slot to call when the request is satisfied.
cancellable Cancellable object.
io_priority The io priority of the request.
gssize Gio::OutputStream::splice_finish ( const Glib::RefPtr< AsyncResult >&  result  ) 

Finishes an asynchronous stream splice operation.

Parameters:
result A AsyncResult.
Returns:
A gssize of the number of bytes spliced.
gssize Gio::OutputStream::write ( const std::string buffer  ) 

Tries to write count bytes from buffer into the stream.

Will block during the operation.

If string that is larger than MAXSSIZE bytes will cause a Gio::Error with INVALID_ARGUMENT to be thrown.

On success, the number of bytes written to the stream is returned. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial i/o error, or if the there is not enough storage in the stream. All writes either block until at least one byte is written, so zero is never returned (unless count is zero).

On error -1 is returned.

Parameters:
buffer The buffer containing the data to write.
Returns:
Number of bytes written, or -1 on error.
gssize Gio::OutputStream::write ( const std::string buffer,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

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

On success, the number of bytes written to the stream is returned. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial i/o error, or if the there is not enough storage in the stream. All writes either block until at least one byte is written, so zero is never returned (unless count is zero).

On error -1 is returned.

Parameters:
buffer The buffer containing the data to write.
cancellable Cancellable object.
Returns:
Number of bytes written, or -1 on error.
gssize Gio::OutputStream::write ( const void *  buffer,
gsize  count 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

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

On success, the number of bytes written to the stream is returned. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial i/o error, or if the there is not enough storage in the stream. All writes either block until at least one byte is written, so zero is never returned (unless count is zero).

On error -1 is returned.

Parameters:
buffer The buffer containing the data to write.
count The number of bytes to write.
Returns:
Number of bytes written, or -1 on error.
gssize Gio::OutputStream::write ( const void *  buffer,
gsize  count,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

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

On success, the number of bytes written to the stream is returned. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial i/o error, or if there is not enough storage in the stream. All writes either block until at least one byte is written, so zero is never returned (unless count is zero).

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:
buffer The buffer containing the data to write.
count The number of bytes to write.
cancellable Cancellable object.
Returns:
Number of bytes written, or -1 on error.
bool Gio::OutputStream::write_all ( const std::string buffer,
gsize &  bytes_written 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

This function is similar to write(), except it tries to write as many bytes as requested, only stopping on an error.

On a successful write of count bytes, true is returned, and bytes_written is set to count .

If there is an error during the operation false is returned and error is set to indicate the error status, bytes_written is updated to contain the number of bytes written into the stream before the error occured.

Parameters:
buffer The buffer containing the data to write.
bytes_written Location to store the number of bytes that was written to the stream.
Returns:
true on success, false if there was an error.
bool Gio::OutputStream::write_all ( const std::string buffer,
gsize &  bytes_written,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

This function is similar to write(), except it tries to write as many bytes as requested, only stopping on an error.

On a successful write of count bytes, true is returned, and bytes_written is set to count .

If there is an error during the operation false is returned and error is set to indicate the error status, bytes_written is updated to contain the number of bytes written into the stream before the error occured.

Parameters:
buffer The buffer containing the data to write.
bytes_written Location to store the number of bytes that was written to the stream.
cancellable Cancellable object.
Returns:
true on success, false if there was an error.
bool Gio::OutputStream::write_all ( const void *  buffer,
gsize  count,
gsize &  bytes_written 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

This function is similar to write(), except it tries to write as many bytes as requested, only stopping on an error.

On a successful write of count bytes, true is returned, and bytes_written is set to count .

If there is an error during the operation false is returned and error is set to indicate the error status, bytes_written is updated to contain the number of bytes written into the stream before the error occured.

Parameters:
buffer The buffer containing the data to write.
count The number of bytes to write.
bytes_written Location to store the number of bytes that was written to the stream.
Returns:
true on success, false if there was an error.
bool Gio::OutputStream::write_all ( const void *  buffer,
gsize  count,
gsize &  bytes_written,
const Glib::RefPtr< Cancellable >&  cancellable 
)

Tries to write count bytes from buffer into the stream.

Will block during the operation.

This function is similar to g_output_stream_write(), except it tries to write as many bytes as requested, only stopping on an error.

On a successful write of count bytes, true is returned, and bytes_written is set to count.

If there is an error during the operation false is returned and error is set to indicate the error status, bytes_written is updated to contain the number of bytes written into the stream before the error occurred.

Parameters:
buffer The buffer containing the data to write.
count The number of bytes to write.
bytes_written Location to store the number of bytes that was written to the stream.
cancellable Optional Cancellable object, 0 to ignore.
Returns:
true on success, false if there was an error.
void Gio::OutputStream::write_async ( const void *  buffer,
gsize  count,
const SlotAsyncReady slot,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous write of count bytes from buffer into the stream.

When the operation is finished slot will be called. You can then call write_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 written will be passed to the callback slot. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial I/O error, but generally we try to write as many bytes as requested.

Any outstanding I/O request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is Glib::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.

For the synchronous, blocking version of this function, see write().

Parameters:
buffer The buffer containing the data to write.
count The number of bytes to write
slot Callback slot to call when the request is satisfied.
io_priority The io priority of the request.
void Gio::OutputStream::write_async ( const void *  buffer,
gsize  count,
const SlotAsyncReady slot,
const Glib::RefPtr< Cancellable >&  cancellable,
int  io_priority = Glib::PRIORITY_DEFAULT 
)

Request an asynchronous write of count bytes from buffer into the stream.

When the operation is finished slot will be called. You can then call write_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 NVALID_ARGUMENT to be thrown.

On success, the number of bytes written will be passed to the callback slot. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial I/O error, but generally we try to write as many bytes as requested.

Any outstanding I/O request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is Glib::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.

For the synchronous, blocking version of this function, see write().

Parameters:
buffer The buffer containing the data to write.
count The number of bytes to write
slot Callback slot to call when the request is satisfied.
cancellable Cancellable object.
io_priority The io priority of the request.
gssize Gio::OutputStream::write_finish ( const Glib::RefPtr< AsyncResult >&  result  ) 

Finishes a stream write operation.

Parameters:
result A AsyncResult.
Returns:
A gssize containing the number of bytes written to the stream.

Friends And Related Function Documentation

Glib::RefPtr< Gio::OutputStream > wrap ( GOutputStream *  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.

Generated on Mon May 3 23:46:28 2010 for glibmm by  doxygen 1.6.1