-\section{\class{wxStreamBuffer}}\label{wxstreambuf}
+\section{\class{wxStreamBuffer}}\label{wxstreambuffer}
\wxheading{Derived from}
None
+\wxheading{Include files}
+
+<wx/stream.h>
+
\wxheading{See also}
\helpref{wxStreamBase}{wxstreambase}
% -----------
% ctor & dtor
% -----------
-\membersection{wxStreamBuffer::wxStreamBuffer}
+\membersection{wxStreamBuffer::wxStreamBuffer}\label{wxstreambufconst}
\func{}{wxStreamBuffer}{\param{wxStreamBase\&}{ stream}, \param{BufMode}{ mode}}
and \it{mode} as the IO mode. \it{mode} can be: wxStreamBuffer::read,
wxStreamBuffer::write, wxStreamBuffer::read\_write.
-\membersection{wxStreamBuffer::wxStreamBuffer}
+
+One stream can have many stream buffers but only one is used internally to
+pass IO call (e.g. wxInputStream::Read() -> wxStreamBuffer::Read()), but you
+can call directly wxStreamBuffer::Read without any problems. Note that
+all errors and messages linked to the stream are stored in the stream, not
+the stream buffers:
+
+\begin{verbatim}
+ streambuffer.Read(...);
+ streambuffer2.Read(...); /* This call erases previous error messages set by
+ ``streambuffer'' */
+\end{verbatim}
\func{}{wxStreamBuffer}{\param{BufMode}{ mode}}
-Constructor, creates a new empty stream buffer which won't flush any datas
+Constructor, creates a new empty stream buffer which won't flush any data
to a stream. \it{mode} specifies the type of the buffer (read, write, read\_write).
+This stream buffer has the advantage to be stream independent and to
+work only on memory buffers but it is still compatible with the rest of the
+wxStream classes. You can write, read to this special stream and it will
+grow (if it is allowed by the user) its internal buffer. Briefly, it has all
+functionality of a ``normal'' stream.
-\membersection{wxStreamBuffer::wxStreamBuffer}
+\wxheading{Warning}
-\func{}{wxStreamBuffer}{\param{const wxStreamBase\&}{ buffer}}
+The "read\_write" mode may not work: it isn't completely finished.
-Constructor, creates a new stream buffer from the specified stream \it{buffer}.
+\func{}{wxStreamBuffer}{\param{const wxStreamBuffer\&}{buffer}}
+
+Constructor. It initializes the stream buffer with the data of the specified
+stream buffer. The new stream buffer has the same attributes, size, position
+and they share the same buffer. This will cause problems if the stream to
+which the stream buffer belong is destroyed and the newly cloned stream
+buffer continues to be used, trying to call functions in the (destroyed)
+stream. It is advised to use this feature only in very local area of the
+program.
+
+\wxheading{See also}
+
+\helpref{wxStreamBuffer:SetBufferIO}{wxstreambuffersetbufferio}
\membersection{wxStreamBuffer::\destruct{wxStreamBuffer}}
-\func{}{\destruct{wxStreamBuffer}}
+\func{}{wxStreamBuffer}{\destruct{wxStreamBuffer}}
-Destructor, destroys the stream buffer.
+Destructor. It finalizes all IO calls and frees all internal buffers if
+necessary.
% -----------
% Filtered IO
% -----------
-\membersection{wxStreamBuffer::Read}\label{wxstreambufread}
+\membersection{wxStreamBuffer::Read}\label{wxstreambufferread}
\func{size\_t}{Read}{\param{void *}{buffer}, \param{size\_t }{size}}
-Reads a block of the specified \it{size} and stores datas in \it{buffer}.
+Reads a block of the specified {\it size} and stores the data in {\it buffer}.
+This function tries to read from the buffer first and if more data has been
+requested, reads more data from the associated stream and updates the buffer
+accordingly until all requested data is read.
\wxheading{Return value}
-It returns the real read size. If returned size is different of the specified
-\it{size}, an error occured and should be tested using
-\helpref{GetError}{wxstreambasegeterror}.
-
-\membersection{wxStreamBuffer::Read}\label{wxstreambufreadbuf}
+It returns the size of the data read. If thereturned size is different of the specified
+{\it size}, an error has occured and should be tested using
+\helpref{LastError}{wxstreambaselasterror}.
\func{size\_t}{Read}{\param{wxStreamBuffer *}{buffer}}
-Reads a \it{buffer}. The function returns when \it{buffer} is full or
-when there aren't datas anymore in the current buffer.
-
-\membersection{wxStreamBuffer::Write}
+Reads a \it{buffer}. The function returns when \it{buffer} is full or when there isn't
+data anymore in the current buffer.
-\func{size\_t}{Write}{\param{const void *}{buffer}, \param{size\_t }{size}}
+\wxheading{See also}
-Writes a block of the specified \it{size} using datas of \it{buffer}.
+\helpref{wxStreamBuffer::Write}{wxstreambufferwrite}
-\membersection{wxStreamBuffer::Write}
+\membersection{wxStreamBuffer::Write}\label{wxstreambufferwrite}
-\func{size\_t}{Write}{\param{wxStreamBuffer *}{buffer}}
+\func{size\_t}{Write}{\param{const void *}{buffer}, \param{size\_t }{size}}
-See \helpref{Read}{wxstreambufreadbuf}
+Writes a block of the specified \it{size} using datas of \it{buffer}. The datas
+are cached in a buffer before being sent in one block to the stream.
-\membersection{wxStreamBuffer::WriteBack}
+\func{size\_t}{Write}{\param{wxStreamBuffer *}{buffer}}
-\func{size\_t}{WriteBack}{\param{const char *}{buffer}, \param{size\_t}{ size}}
+See \helpref{Read}{wxstreambufferread}.
-This function is only useful in ``read'' mode. It puts the specified \it{buffer}
-in the input queue of the stream buf. By this way, the next
-\helpref{Read}{wxstreambufread} call will first use these datas.
+\membersection{wxStreamBuffer::GetChar}
-\membersection{wxStreamBuffer::WriteBack}
+\func{char}{GetChar}{\void}
-\func{size\_t}{WriteBack}{\param{char }{c}}
+Gets a single char from the stream buffer. It acts like the Read call.
-As for the previous function, it puts the specified byte in the input queue of the
-stream buffer.
+\wxheading{Problem}
-\membersection{wxStreamBuffer::GetChar}
+You aren't directly notified if an error occured during the IO call.
-\func{char}{GetChar}{\void}
+\wxheading{See also}
-Gets a single char from the stream buffer.
+\helpref{wxStreamBuffer::Read}{wxstreambufferread}
\membersection{wxStreamBuffer::PutChar}
Puts a single char to the stream buffer.
+\wxheading{Problem}
+
+You aren't directly notified if an error occured during the IO call.
+
+\wxheading{See also}
+
+\helpref{wxStreamBuffer::Read}{wxstreambufferwrite}
+
\membersection{wxStreamBuffer::Tell}
\constfunc{off\_t}{Tell}{\void}
-Gets the current position in the \it{stream}.
+Gets the current position in the stream. This position is calculated from
+the \it{real} position in the stream and from the internal buffer position: so
+it gives you the position in the \it{real} stream counted from the start of
+the stream.
-\membersection{wxStreamBuffer::Seek}
+\wxheading{Return value}
+
+Returns the current position in the stream if possible, wxInvalidOffset in the
+other case.
+
+\membersection{wxStreamBuffer::Seek}\label{wxstreambufferseek}
\func{off\_t}{Seek}{\param{off\_t }{pos}, \param{wxSeekMode }{mode}}
-Changes the current position. (TODO)
+Changes the current position.
+
+\it{mode} may be one of the following:
+
+\twocolwidtha{5cm}
+\begin{twocollist}\itemsep=0pt
+\twocolitem{{\bf wxFromStart}}{The position is counted from the start of the stream.}
+\twocolitem{{\bf wxFromCurrent}}{The position is counted from the current position of the stream.}
+\twocolitem{{\bf wxFromEnd}}{The position is counted from the end of the stream.}
+\end{twocollist}
+
+\wxheading{Return value}
+
+Upon successful completion, it returns the new offset as measured in bytes from
+the beginning of the stream. Otherwise, it returns wxInvalidOffset.
% --------------
% Buffer control
\func{void}{ResetBuffer}{\void}
-Frees all internal buffers and resets to initial state all variables.
+Resets to the initial state variables concerning the buffer.
-\membersection{wxStreamBuffer::SetBufferIO}
+\membersection{wxStreamBuffer::SetBufferIO}\label{wxstreambuffersetbufferio}
-\func{void}{SetBufferIO}{\param{char *}{ buffer\_start}, \param{char *}{ buffer\_end}}
+\func{void}{SetBufferIO}{\param{char*}{ buffer\_start}, \param{char*}{ buffer\_end}}
Specifies which pointers to use for stream buffering. You need to pass a pointer on the
-start of the buffer end and another on the end.
+start of the buffer end and another on the end. The object will use this buffer
+to cache stream data. It may be used also as a source/destination buffer when
+you create an empty stream buffer (See \helpref{wxStreamBuffer::wxStreamBuffer}{wxstreambufconst}).
+
+\wxheading{Remarks}
+
+When you use this function, you'll have to destroy the IO buffers yourself
+after the stream buffer is destroyed or don't use it anymore.
+In the case you use it with an empty buffer, the stream buffer will not resize
+it when it is full.
+
+\wxheading{See also}
-\membersection{wxStreamBuffer::SetBufferIO}
+\helpref{wxStreamBuffer constructor}{wxstreambufconst}\\
+\helpref{wxStreamBuffer::Fixed}{wxstreambufferfixed}\\
+\helpref{wxStreamBuffer::Flushable}{wxstreambufferflushable}
\func{void}{SetBufferIO}{\param{size\_t}{ bufsize}}
-Changes the size of the current IO buffer.
+Destroys or invalidates the previous IO buffer and allocates a new one of the
+specified size.
+
+\wxheading{Warning}
+
+All previous pointers aren't valid anymore.
+
+\wxheading{Remark}
+
+The created IO buffer is growable by the object.
+
+\wxheading{See also}
+
+\helpref{wxStreamBuffer::Fixed}{wxstreambufferfixed}\\
+\helpref{wxStreamBuffer::Flushable}{wxstreambufferflushable}
\membersection{wxStreamBuffer::GetBufferStart}
\constfunc{off\_t}{GetIntPosition}{\void}
-Returns the current position in the stream buffer.
+Returns the current position (counted in bytes) in the stream buffer.
\membersection{wxStreamBuffer::SetIntPosition}
\func{void}{SetIntPosition}{\void}
-Sets the current position in the stream buffer.
+Sets the current position (in bytes) in the stream buffer.
+
+\wxheading{Warning}
+
+Since it is a very low-level function, there is no check on the position:
+specify an invalid position can induce unexpected results.
\membersection{wxStreamBuffer::GetLastAccess}
Returns the amount of bytes read during the last IO call to the parent stream.
-\membersection{wxStreamBuffer::Fixed}
+\membersection{wxStreamBuffer::Fixed}\label{wxstreambufferfixed}
\func{void}{Fixed}{\param{bool}{ fixed}}
Toggles the fixed flag. Usually this flag is toggled at the same time as
-\it{flushable}. This flag allows (when it is FALSE) or forbids (when it is TRUE)
-the stream buffer to resize dynamically the IO buffer.
+\it{flushable}. This flag allows (when it has the FALSE value) or forbids
+(when it has the TRUE value) the stream buffer to resize dynamically the IO buffer.
+
+\wxheading{See also}
+
+\helpref{wxStreamBuffer::SetBufferIO}{wxstreambuffersetbufferio}
-\membersection{wxStreamBuffer::Flushable}
+\membersection{wxStreamBuffer::Flushable}\label{wxstreambufferflushable}
\func{void}{Flushable}{\param{bool}{ flushable}}
% --------------
\membersection{wxStreamBuffer::Stream}
-\func{wxStreamBase *}{Stream}{\void}
+\func{wxStreamBase*}{Stream}{\void}
-Returns the stream parent of the stream buffer.
+Returns the parent stream of the stream buffer.
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