HOW-TO return CLOB datatype in PL/SQL

CREATE OR REPLACE PROCEDURE Clobtestproc(o_clob OUT CLOB)
AS
tmpclob CLOB;
tmpxml VARCHAR2(100);
BEGIN
tmpxml :='ABC';
DBMS_LOB.createtemporary(tmpclob, FALSE);
DBMS_LOB.WRITE (tmpclob,LENGTH (tmpxml), 1, tmpxml);
o_CLOB := tmpclob;
DBMS_LOB.freetemporary(tmpclob);
END;
/