/////////////////////////////////////////////////////////////////////////////
// Name: stream.h
-// Purpose: topic overview
+// Purpose: stream classes overview
// Author: wxWidgets team
// RCS-ID: $Id$
-// Licence: wxWindows license
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
/**
-@page overview_stream wxStreams Overview
+@page overview_stream Stream classes overview
Classes:
@li wxStreamBase
@li wxOutputStream
@li wxFilterInputStream
@li wxFilterOutputStream
+@li wxFileInputStream
+@li wxFileOutputStream
+@li wxTextInputStream
+@li wxTextOutputStream
+@li wxDataInputStream
+@li wxDataOutputStream
@li @ref overview_stream_intro
@li @ref overview_stream_example
@section overview_stream_intro Introduction
-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.
+@subsection overview_stream_intro_std wxWidgets and Standard Streams
-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++.
+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).
-wxStreams is divided in two main parts:
+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).
+
+
+@subsection overview_stream_intro_overview Stream Classes
+
+wxStream classes are divided in two main groups:
@li The core: wxStreamBase, wxStreamBuffer, wxInputStream, wxOutputStream,
- wxFilterIn/OutputStream
-@li The "IO" classes: wxSocketIn/OutputStream, wxDataIn/OutputStream,
- wxFileIn/OutputStream, ...
+ 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
-inherit from it.
+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
-have always one autoinitialized 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 but it is for write-only streams.
+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.
-wxFilterIn/OutputStream is the base class definition for stream filtering.
+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.
+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(...)).
+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
// 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
+// 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);
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