How to convert HBufC to TBuf ???

here is an example

const TInt KLength=200;//sample length
HBufC* buf=HBufC::NewLC(256);
// .... add some text to buf

TBuf<256> tbuf(*buf);

//..

CelanupStack::PopAndDestroy(buf);

Note that you should be careful with the lengths - make sure that the length of the Hbuf string does not exceed that of the TBuf.