/////////////////////////////////////////////////////////////////////////////
-// Name: stream
-// Purpose: topic overview
+// Name: stream.h
+// Purpose: stream classes overview
// Author: wxWidgets team
-// RCS-ID: $Id$
-// Licence: wxWindows license
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
-/*!
-
- @page stream_overview wxStreams overview
-
- Classes: #wxStreamBase,
- #wxStreamBuffer, #wxInputStream,
- #wxOutputStream,
- #wxFilterInputStream,
- #wxFilterOutputStream
- @b Purpose of wxStream
- Standard C++ streams can cause problems on several platforms:
- they work quite well in most cases, but in the multi-threaded case, for example,
- they have many problems. Some Borland compilers refuse to work at all
- with them and using iostreams on Linux makes writing programs that are
- binary compatible across different Linux distributions, impossible.
- Therefore, wxStreams have been added to wxWidgets so that applications can
- reliably compile and run on all supported platforms without dependence on a
- particular release of libg++.
- wxStreams is divided in two main parts:
-
-
- the core: wxStreamBase, wxStreamBuffer, wxInputStream, wxOutputStream,
- wxFilterIn/OutputStream
- the "IO" classes: wxSocketIn/OutputStream, wxDataIn/OutputStream, wxFileIn/OutputStream, ...
-
-
- wxStreamBase is the base definition of a stream. It defines, for example,
- the API of OnSysRead, OnSysWrite, OnSysSeek and OnSysTell. These functions
- are really implemented by the "IO" classes.
- wxInputStream and wxOutputStream inherit from it.
- wxStreamBuffer is a cache manager for wxStreamBase: it manages a stream buffer
- linked to a stream. One stream can have multiple stream buffers but one stream
- have always one autoinitialized stream buffer.
- wxInputStream is the base class for read-only streams. It implements Read,
- SeekI (I for Input), and all read or IO generic related functions.
- wxOutputStream does the same thing but it is for write-only streams.
- wxFilterIn/OutputStream is the base class definition for stream filtering.
- Stream filtering means a stream which does no syscall but filters data
- which are passed to it and then pass them to another stream.
- For example, wxZLibInputStream is an inline stream decompressor.
- The "IO" classes implements the specific parts of the stream. This could be
- nothing in the case of wxMemoryIn/OutputStream which bases itself on
- wxStreamBuffer. This could also be a simple link to the a @true syscall
- (for example read(...), write(...)).
- @b Generic usage: an example
- Usage is simple. We can take the example of wxFileInputStream and here is some sample
- code:
-
- @code
- ...
- // The constructor initializes the stream buffer and open the file descriptor
- // associated to the name of the file.
- wxFileInputStream in_stream("the_file_to_be_read");
-
- // Ok, read some bytes ... nb_datas is expressed in bytes.
- in_stream.Read(data, nb_datas);
- if (in_stream.LastError() != wxSTREAM_NOERROR) {
+/**
+
+@page overview_stream Stream Classes Overview
+
+@tableofcontents
+
+wxWidgets provides its own set of stream classes in order to support platforms
+not providing standard C++ streams implementation and also to make it possible
+to provide binary versions of wxWidgets application not depending on any
+particular standard library version. The wxWidgets stream classes also provide
+some functionality not available in the standard library such as support for
+several compression formats and possibility to work with sockets or text
+controls (for output only in the latter case).
+
+Nevertheless wxWidgets programs can also use standard stream classes and are
+encouraged to do so if the above considerations don't apply. Moreover,
+wxStdInputStream and wxStdOutputStream classes are provided to provide a degree
+of interoperability between the two and make it possible to use any wxWidgets
+stream as a standard stream (the converse possibility to use a standard stream
+as a wxWidgets stream is planned for a future release).
+
+
+
+@section overview_stream_classes Stream Classes
+
+wxStream classes are divided in two main groups:
+
+@li The core: wxStreamBase, wxStreamBuffer, wxInputStream, wxOutputStream,
+ wxFilterInputStream, wxFilterOutputStream
+@li The "IO" classes: wxSocketInputStream, wxSocketOutputStream,
+ wxFileInputStream, wxFileOutputStream, ...
+@li Classes for reading text or binary data from a particular stream
+ such as wxTextInputStream, wxTextOutputStream, wxDataInputStream
+ and wxDataOutputStream
+
+wxStreamBase is the base definition of a stream. It defines, for example, the
+API of OnSysRead(), OnSysWrite(), OnSysSeek() and OnSysTell(). These functions are
+really implemented by the "IO" classes.
+wxInputStream and wxOutputStream classes inherit from wxStreamBase and provide
+specialized methods for input and output.
+
+wxStreamBuffer is a cache manager for wxStreamBase: it manages a stream buffer
+linked to a stream. One stream can have multiple stream buffers but one stream
+has always one autoinitialized stream buffer.
+
+wxInputStream is the base class for read-only streams. It implements Read(),
+SeekI() (I for Input), and all read or IO generic related functions.
+wxOutputStream does the same thing for write-only streams.
+
+wxFilterInputStream and wxFileterOutputStream are the base class definitions for
+stream filtering.
+Stream filtering means a stream which does no syscall but filters data which
+are passed to it and then pass them to another stream.
+For example, wxZLibInputStream is an inline stream decompressor.
+
+The "IO" classes implements the specific parts of the stream. This could be
+nothing in the case of wxMemoryInputStream and wxMemoryOutputStream which base
+themselves on wxStreamBuffer.
+This could also be a simple link to the true syscall (for example read(...), write(...)).
+
+
+@section overview_stream_example Example
+
+Usage is simple. We can take the example of wxFileInputStream and here is some
+sample code:
+
+@code
+...
+// The constructor initializes the stream buffer and open the file descriptor
+// associated to the name of the file.
+wxFileInputStream in_stream("the_file_to_be_read");
+
+// Ok, read some bytes ... nb_datas is expressed in bytes.
+in_stream.Read(data, nb_datas);
+if (in_stream.LastError() != wxSTREAM_NOERROR) {
// Oh oh, something bad happens.
// For a complete list, look into the documentation at wxStreamBase.
- }
-
- // You can also inline all like this.
- if (in_stream.Read(data, nb_datas).LastError() != wxSTREAM_NOERROR) {
+}
+
+// You can also inline all like this.
+if (in_stream.Read(data, nb_datas).LastError() != wxSTREAM_NOERROR) {
// Do something.
- }
-
- // You can also get the last number of bytes REALLY put into the buffer.
- size_t really_read = in_stream.LastRead();
-
- // Ok, moves to the beginning of the stream. SeekI returns the last position
- // in the stream counted from the beginning.
- off_t old_position = in_stream.SeekI(0, wxFromBeginning);
-
- // What is my current position ?
- off_t position = in_stream.TellI();
-
- // wxFileInputStream will close the file descriptor on destruction.
- @endcode
-
- */
-
-
+}
+
+// You can also get the last number of bytes REALLY put into the buffer.
+size_t really_read = in_stream.LastRead();
+
+// Ok, moves to the beginning of the stream. SeekI returns the last position
+// in the stream counted from the beginning.
+off_t old_position = in_stream.SeekI(0, wxFromBeginning);
+
+// What is my current position ?
+off_t position = in_stream.TellI();
+
+// wxFileInputStream will close the file descriptor on destruction.
+@endcode
+
+*/
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