Problem write data to file with RFileWriteStream ! Please help me ! Thanks!

Hi all !
I want to write data from file a.txt to b.txt by using "RFileWriteStream" and "RFileReadStream".But data doesn't write into b.txt file . Please help me to correct my code ! Thanks very much !.
//=============  This is my code ========
void CView01::WriteData()
{
      //=====   Connect to File server
      RFs aFs;
      User::LeaveIfError(aFs.Connect());
      CleanupClosePushL(aFs);
      _LIT( Filepath02, "C:\\b.txt");
      _LIT( Filepath01, "C:\\a.txt");

      //=====  Object for reading stream
      RFileReadStream fRead;
      //=====   Open a read stream
      User::LeaveIfError(fRead.Open(aFs, Filepath01, EFileRead));
      TInt8 pBuf1 = fRead.ReadInt8L();
      TInt8 pBuf2 = fRead.ReadInt8L();
      TInt8 pBuf3 = fRead.ReadInt8L();

      //=====   Write to File
      RFileWriteStream fWrite;
      //=====   Open a write stream
      User::LeaveIfError(fWrite.Create( aFs, Filepath02, EFileWrite ) );
      fWrite.WriteInt8L(pBuf1);
      fWrite.WriteInt8L(pBuf2);
      fWrite.WriteInt8L(pBuf3);

     CleanupStack::PopAndDestroy(&aFs);

}
//=========== doctinh113114===========