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Read method

Project: Stream Extension Classes

Unit: PJIStreams

Classes: TPJIStreamWrapper, TPJHandleIStreamWrapper, TPJFileIStream

Applies to: ~>3.0

function Read(pv: Pointer; cb: Longint; pcbRead: PLongint): HResult;
  virtual; stdcall;


Reads a specified number of bytes from the wrapped stream into memory starting at the current seek pointer. The seek pointer is incremented by the number of bytes read.




If the requested number of bytes are available in the wrapped stream then pv^ receives cb bytes and pcbRead^ is set equal to cb. If there is insufficient data remaining in the wrapped stream to fulfil the request then any remaining bytes are read from the stream into pv^ and pcbRead^ will be less than cb. If the stream is at the end when the request is made then no data is copied into pv^ and pcbRead^ is set to zero.

The buffer pointed to by pv must have capacity of at least cb bytes.