OutputStream

OutputStream 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.

Inheritance Diagram

Inheritance diagram for class OutputStream

Known Subclasses

CountingOutputStream, FFileOutputStream, FileOutputStream, FilterOutputStream, MemoryOutputStream, SocketOutputStream, StringOutputStream, TempFileOutputStream

Methods Summary

__init__	Creates a dummy OutputStream object.
Close	Closes the stream, returning False if an error occurs.
LastWrite	Returns the number of bytes written during the last Write .
PutC	Puts the specified character in the output queue and increments the stream position.
SeekO	Changes the stream current position.
TellO	Returns the current stream position.
Write	Writes up to the specified amount of bytes using the data of buffer.
close
eof
flush
seek
tell
write

Class API

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class OutputStream(StreamBase)

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

Possible constructors:

OutputStream()

Methods

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__init__(self)

Creates a dummy OutputStream object.

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Close(self)

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.

Return type:bool

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LastWrite(self)

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.

Return type:int

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PutC(self, c)

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

Parameters:c (int) –

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SeekO(self, pos, mode=FromStart)

Changes the stream current position.

Parameters:

• pos (int) – Offset to seek to.
• mode (SeekMode) – One of FromStart, FromEnd, FromCurrent.

Return type:

int

Returns:

The new stream position or InvalidOffset on error.

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TellO(self)

Returns the current stream position.

Return type:int

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Write(self, *args, **kw)

Overloaded Implementations:

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Write (self, buffer, size)

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.

Parameters:

• buffer –
• size (int) –

Return type:

OutputStream

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Write (self, 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.

Parameters:stream_in (InputStream) – Return type: OutputStream

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close(self)

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eof(self)

Return type:bool

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flush(self)

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seek(self, offset, whence=0)

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tell(self)

Return type:int

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write(self, data)