Version: 3.1.1
wxOutputStream Class Reference

#include <wx/stream.h>

+ Inheritance diagram for wxOutputStream:

Detailed Description

wxOutputStream is an abstract base class which may not be used directly.

It is the base class of all streams which provide a Write() function, i.e. which can be used to output data (e.g. to a file, to a socket, etc).

If you want to create your own output stream, you'll need to derive from this class and implement the protected OnSysWrite() function only.

Library:  wxBase
Category:  Streams

Public Member Functions

 wxOutputStream ()
 Creates a dummy wxOutputStream object. More...
 
virtual ~wxOutputStream ()
 Destructor. More...
 
virtual bool Close ()
 Closes the stream, returning false if an error occurs. More...
 
virtual size_t LastWrite () const
 Returns the number of bytes written during the last Write(). More...
 
void PutC (char c)
 Puts the specified character in the output queue and increments the stream position. More...
 
virtual wxFileOffset SeekO (wxFileOffset pos, wxSeekMode mode=wxFromStart)
 Changes the stream current position. More...
 
virtual wxFileOffset TellO () const
 Returns the current stream position. More...
 
virtual wxOutputStreamWrite (const void *buffer, size_t size)
 Writes up to the specified amount of bytes using the data of buffer. More...
 
wxOutputStreamWrite (wxInputStream &stream_in)
 Reads data from the specified input stream and stores them in the current stream. More...
 
bool WriteAll (const void *buffer, size_t size)
 Writes exactly the specified number of bytes from the buffer. More...
 
- Public Member Functions inherited from wxStreamBase
 wxStreamBase ()
 Creates a dummy stream object. More...
 
virtual ~wxStreamBase ()
 Destructor. More...
 
wxStreamError GetLastError () const
 This function returns the last error. More...
 
virtual wxFileOffset GetLength () const
 Returns the length of the stream in bytes. More...
 
virtual size_t GetSize () const
 This function returns the size of the stream. More...
 
virtual bool IsOk () const
 Returns true if no error occurred on the stream. More...
 
virtual bool IsSeekable () const
 Returns true if the stream supports seeking to arbitrary offsets. More...
 
void Reset (wxStreamError error=wxSTREAM_NO_ERROR)
 Resets the stream state. More...
 
bool operator! () const
 Returns the opposite of IsOk(). More...
 

Protected Member Functions

size_t OnSysWrite (const void *buffer, size_t bufsize)
 Internal function. More...
 
- Protected Member Functions inherited from wxStreamBase
virtual wxFileOffset OnSysSeek (wxFileOffset pos, wxSeekMode mode)
 Internal function. More...
 
virtual wxFileOffset OnSysTell () const
 Internal function. More...
 

Constructor & Destructor Documentation

wxOutputStream::wxOutputStream ( )

Creates a dummy wxOutputStream object.

virtual wxOutputStream::~wxOutputStream ( )
virtual

Destructor.

Member Function Documentation

virtual bool wxOutputStream::Close ( )
virtual

Closes the stream, returning false if an error occurs.

The stream is closed implicitly in the destructor if Close() is not called explicitly.

If this stream wraps another stream or some other resource such as a file, then the underlying resource is closed too if it is owned by this stream, or left open otherwise.

Reimplemented in wxZipOutputStream, wxTarOutputStream, and wxArchiveOutputStream.

virtual size_t wxOutputStream::LastWrite ( ) const
virtual

Returns the number of bytes written during the last Write().

It may return 0 even if there is no error on the stream if it is only temporarily impossible to write to it.

size_t wxOutputStream::OnSysWrite ( const void *  buffer,
size_t  bufsize 
)
protected

Internal function.

It is called when the stream wants to write data of the specified size bufsize into the given buffer.

It should return the size that was actually wrote (which maybe zero if bufsize is zero or if an error occurred; in this last case the internal variable m_lasterror should be appropriately set).

void wxOutputStream::PutC ( char  c)

Puts the specified character in the output queue and increments the stream position.

virtual wxFileOffset wxOutputStream::SeekO ( wxFileOffset  pos,
wxSeekMode  mode = wxFromStart 
)
virtual

Changes the stream current position.

Parameters
posOffset to seek to.
modeOne of wxFromStart, wxFromEnd, wxFromCurrent.
Returns
The new stream position or wxInvalidOffset on error.

Reimplemented in wxBufferedOutputStream.

virtual wxFileOffset wxOutputStream::TellO ( ) const
virtual

Returns the current stream position.

virtual wxOutputStream& wxOutputStream::Write ( const void *  buffer,
size_t  size 
)
virtual

Writes up to the specified amount of bytes using the data of buffer.

Note that not all data can always be written so you must check the number of bytes really written to the stream using LastWrite() when this function returns.

In some cases (for example a write end of a pipe which is currently full) it is even possible that there is no errors and zero bytes have been written. This function returns a reference on the current object, so the user can test any states of the stream right away.

wxOutputStream& wxOutputStream::Write ( wxInputStream stream_in)

Reads data from the specified input stream and stores them in the current stream.

The data is read until an error is raised by one of the two streams.

bool wxOutputStream::WriteAll ( const void *  buffer,
size_t  size 
)

Writes exactly the specified number of bytes from the buffer.

Returns true if exactly size bytes were written. Otherwise, returns false and LastWrite() should be used to retrieve the exact amount of the data written if necessary.

This method uses repeated calls to Write() (which may return writing only part of the data) if necessary.

Since
2.9.5