## wxStreamBase

This class is the base class of most stream related classes in wxWidgets. It must not be used directly.

Derived from

None

Include files

<wx/stream.h>

See also

wxStreamBuffer

Members

wxStreamBase::wxStreamBase
wxStreamBase::~wxStreamBase
wxStreamBase::GetLength
wxStreamBase::GetLastError
wxStreamBase::GetSize
wxStreamBase::IsOk
wxStreamBase::IsSeekable
wxStreamBase::OnSysRead
wxStreamBase::OnSysSeek
wxStreamBase::OnSysTell
wxStreamBase::OnSysWrite

### wxStreamBase::wxStreamBase

wxStreamBase()

Creates a dummy stream object. It doesn't do anything.

### wxStreamBase::~wxStreamBase

~wxStreamBase()

Destructor.

### wxStreamBase::GetLength

wxFileOffset GetLength() const

Returns the length of the stream in bytes. If the length cannot be determined (this is always the case for socket streams for example), returns `wxInvalidOffset`.

This function is new since wxWidgets version 2.5.4

### wxStreamBase::GetLastError

wxStreamError GetLastError() const

This function returns the last error.

wxSTREAM_NO_ERROR | No error occurred.
wxSTREAM_EOF | An End-Of-File occurred.
wxSTREAM_WRITE_ERROR | A generic error occurred on the last write call.
wxSTREAM_READ_ERROR | A generic error occurred on the last read call.

### wxStreamBase::GetSize

size_t GetSize() const

GetLength

This function returns the size of the stream. For example, for a file it is the size of the file.

Warning

There are streams which do not have size by definition, such as socket streams. In that cases, GetSize returns 0 so you should always test its return value.

### wxStreamBase::IsOk

virtual bool IsOk() const

Returns true if no error occurred on the stream.

See also

GetLastError

### wxStreamBase::IsSeekable

bool IsSeekable() const

Returns true if the streams supports seeking to arbitrary offsets.

### wxStreamBase::OnSysRead

size_t OnSysRead(void* buffer, size_t bufsize)

Internal function. It is called when the stream wants to read data of the specified size. It should return the size that was actually read.

### wxStreamBase::OnSysSeek

off_t OnSysSeek(off_t pos, wxSeekMode mode)

Internal function. It is called when the stream needs to change the current position.

### wxStreamBase::OnSysTell

off_t OnSysTell() const

Internal function. Is is called when the stream needs to know the real position.

### wxStreamBase::OnSysWrite

size_t OnSysWrite(const void *buffer, size_t bufsize)

See OnSysRead.