Minor tweek for WXPM

[wxWidgets.git] / docs / latex / wx / stream.tex

diff --git a/docs/latex/wx/stream.tex b/docs/latex/wx/stream.tex
index 2715542dddcdaa59afb472740aed676f4e3c9752..95e166b23a3d8621d506438f23b4c654a690c932 100644 (file)
--- a/docs/latex/wx/stream.tex
+++ b/docs/latex/wx/stream.tex
@@ -4,6 +4,10 @@
 
 None
 
 
 None
 

+\wxheading{Include files}
+
+<wx/stream.h>
+

 \wxheading{See also}
 
 \helpref{wxStreamBase}{wxstreambase}
 \wxheading{See also}
 
 \helpref{wxStreamBase}{wxstreambase}


@@ -16,41 +20,92 @@ None
 % -----------
 % ctor & dtor
 % -----------
 % -----------
 % ctor & dtor
 % -----------

-\membersection{wxStreamBuffer::wxStreamBuffer}
+\membersection{wxStreamBuffer::wxStreamBuffer}\label{wxstreambufconst}

 
 \func{}{wxStreamBuffer}{\param{wxStreamBase\&}{ stream}, \param{BufMode}{ mode}}
 
 Constructor, creates a new stream buffer using \it{stream} as a parent stream
 and \it{mode} as the IO mode. \it{mode} can be: wxStreamBuffer::read,
 wxStreamBuffer::write, wxStreamBuffer::read\_write.
 
 \func{}{wxStreamBuffer}{\param{wxStreamBase\&}{ stream}, \param{BufMode}{ mode}}
 
 Constructor, creates a new stream buffer using \it{stream} as a parent stream
 and \it{mode} as the IO mode. \it{mode} can be: wxStreamBuffer::read,
 wxStreamBuffer::write, wxStreamBuffer::read\_write.

+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.
+
+\wxheading{Warning}
+
+All errors and messages linked to the stream are stored in the stream object.

 
 

-\membersection{wxStreamBuffer::wxStreamBuffer}
+\begin{verbatim}
+  streambuffer.Read(...);
+  streambuffer2.Read(...); /* This one 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 data
 
 \func{}{wxStreamBuffer}{\param{BufMode}{ mode}}
 
 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).
+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.
+
+\wxheading{Warning}
+
+The "read\_write" mode may not work: it isn't completely finished.
+You can create "memory" streams by this way:
+
+\begin{verbatim}
+  wxStreamBuffer *sb = new wxStreamBuffer(wxStreamBuffer::read)
+  wxInputStream *input = new wxInputStream(sb);

 
 

-\membersection{wxStreamBuffer::wxStreamBuffer}
+  sb->Fixed(FALSE); // It can change the size of the buffer.

 
 

-\func{}{wxStreamBuffer}{\param{const wxStreamBase\&}{ buffer}}
+  // input is now a read-only memory stream.
+\end{verbatim}
+
+But you should take care when destroying the stream buffer yourself.
+
+\func{}{wxStreamBuffer}{\param{const wxStreamBuffer\&}{buffer}}
+
+Constructor. It initializes the stream buffer with the data of the specified
+stream buffer. The new stream buffer is nearly exactly the same as the
+original: it has the same attributes, the same size, the same position, shares
+the same internal buffer. The interresting point is that they can differ
+in the future but the root is the same.
+
+\wxheading{Warning}
+
+The fact that the two stream buffers shared the same buffer could generate
+segmentation violation if the parent is destroyed and the children continues
+operating. It is advised to use this feature only in very local area of the
+program.
+
+\wxheading{See also}

 
 

-Constructor, creates a new stream buffer from the specified stream \it{buffer}.
+\helpref{wxStreamBuffer:SetBufferIO}{wxstreambuffersetbufferio}

 
 \membersection{wxStreamBuffer::\destruct{wxStreamBuffer}}
 
 \func{}{wxStreamBuffer}{\destruct{wxStreamBuffer}}
 
 
 \membersection{wxStreamBuffer::\destruct{wxStreamBuffer}}
 
 \func{}{wxStreamBuffer}{\destruct{wxStreamBuffer}}
 

-Destructor, destroys the stream buffer.
+Destructor. It finalizes all IO calls and frees all internal buffers if
+necessary. In the case of a children stream buffer, the internal buffer isn't
+freed, this is the job of the parent.
+The "Write-Back" buffer is freed.

 
 % -----------
 % Filtered IO
 % -----------
 
 % -----------
 % 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}.
 
 \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}.

+This function uses also the "Write-Back" buffer: in the case there are datas
+waiting in this buffer, they are used before anything else. After that, if there
+are still datas to be read, the stream is read and the stream buffer position
+is incremented.

 
 \wxheading{Return value}
 
 
 \wxheading{Return value}
 


@@ -58,45 +113,39 @@ 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{LastError}{wxstreambaselasterror}.
 
 \it{size}, an error occured and should be tested using 
 \helpref{LastError}{wxstreambaselasterror}.
 

-\membersection{wxStreamBuffer::Read}\label{wxstreambufreadbuf}
+\wxheading{See also}
+
+\helpref{wxStreamBuffer::Write}{wxstreambufferwrite}

 
 \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.
 
 
 \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}
+\membersection{wxStreamBuffer::Write}\label{wxstreambufferwrite}

 
 \func{size\_t}{Write}{\param{const void *}{buffer}, \param{size\_t }{size}}
 
 
 \func{size\_t}{Write}{\param{const void *}{buffer}, \param{size\_t }{size}}
 

-Writes a block of the specified \it{size} using datas of \it{buffer}.
-
-\membersection{wxStreamBuffer::Write}
+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.

 
 \func{size\_t}{Write}{\param{wxStreamBuffer *}{buffer}}
 
 
 \func{size\_t}{Write}{\param{wxStreamBuffer *}{buffer}}
 

-See \helpref{Read}{wxstreambufreadbuf}
-
-\membersection{wxStreamBuffer::WriteBack}
+See \helpref{Read}{wxstreambufferread}.

 
 

-\func{size\_t}{WriteBack}{\param{const char*}{ buffer}, \param{size\_t}{ size}}
+\membersection{wxStreamBuffer::GetChar}

 
 

-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.
+\func{char}{GetChar}{\void}

 
 

-\membersection{wxStreamBuffer::WriteBack}
+Gets a single char from the stream buffer. It acts like the Read call.

 
 

-\func{size\_t}{WriteBack}{\param{char }{c}}
+\wxheading{Problem}

 
 

-As for the previous function, it puts the specified byte in the input queue of the
-stream buffer.
+You aren't directly notified if an error occured during the IO call.

 
 

-\membersection{wxStreamBuffer::GetChar}
-
-\func{char}{GetChar}{\void}
+\wxheading{See also}

 
 

-Gets a single char from the stream buffer.
+\helpref{wxStreamBuffer::Read}{wxstreambufferread}

 
 \membersection{wxStreamBuffer::PutChar}
 
 
 \membersection{wxStreamBuffer::PutChar}
 


@@ -104,17 +153,47 @@ Gets a single char from the stream buffer.
 
 Puts a single char to the stream buffer.
 
 
 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}
 
 \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.
+
+\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}}
 
 
 \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
 
 % --------------
 % Buffer control


@@ -123,20 +202,47 @@ Changes the current position. (TODO)
 
 \func{void}{ResetBuffer}{\void}
 
 
 \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}}
 
 Specifies which pointers to use for stream buffering. You need to pass a pointer on the
 
 \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 grow
+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}}
 
 
 \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}
 
 
 \membersection{wxStreamBuffer::GetBufferStart}
 


@@ -160,13 +266,18 @@ Returns a pointer on the current position of the stream buffer.
 
 \constfunc{off\_t}{GetIntPosition}{\void}
 
 
 \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}
 
 
 \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}
 
 
 \membersection{wxStreamBuffer::GetLastAccess}
 


@@ -174,15 +285,19 @@ Sets the current position in the stream buffer.
 
 Returns the amount of bytes read during the last IO call to the parent stream.
 
 
 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 
 
 \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}}
 
 
 \func{void}{Flushable}{\param{bool}{ flushable}}
 


@@ -214,5 +329,5 @@ Returns the amount of available datas in the buffer.
 
 \func{wxStreamBase*}{Stream}{\void}
 
 
 \func{wxStreamBase*}{Stream}{\void}
 

-Returns the stream parent of the stream buffer.
+Returns the parent stream of the stream buffer.