How to print Attached text file in PO to a Purchase Order Print out ?

function CF_ATTACHFormula return Char is
V_ATTACH Varchar2(32000);
V_LONG_TXT LONG(32000);
begin
  SELECT DLT.LONG_TEXT INTO V_LONG_TXT
  /*AD.SEQ_NUM                  ,
  DCT.USER_NAME               ,
  DAT.USER_NAME               ,
  AD.ATTACHED_DOCUMENT_ID     ,
  DET.USER_ENTITY_NAME        ,
  DAT.NAME                    ,
  D.DOCUMENT_ID               ,
  AD.ENTITY_NAME              ,
  AD.PK1_VALUE                ,
  D.MEDIA_ID                  ,
  D.URL                       ,
  DT.TITLE                    ,
  DLT.LONG_TEXT */
FROM FND_DOCUMENT_DATATYPES DAT,
  FND_DOCUMENT_ENTITIES_TL DET    ,
  FND_DOCUMENTS_TL DT             ,
  FND_DOCUMENTS D                 ,
  FND_DOCUMENT_CATEGORIES_TL DCT  ,
  FND_ATTACHED_DOCUMENTS AD       ,
  FND_DOCUMENTS_LONG_TEXT DLT    ,
  PO_HEADERS_ALL    PHA
WHERE D.DOCUMENT_ID       = AD.DOCUMENT_ID
AND DT.DOCUMENT_ID        = D.DOCUMENT_ID
AND DCT.CATEGORY_ID       = D.CATEGORY_ID
AND D.DATATYPE_ID         = DAT.DATATYPE_ID
AND AD.ENTITY_NAME        = DET.DATA_OBJECT_CODE
AND DLT.MEDIA_ID          = D.MEDIA_ID
AND DAT.NAME              = 'LONG_TEXT'
AND ENTITY_NAME = 'PO_HEADERS'
AND AD.PK1_VALUE  = PHA.PO_HEADER_ID
AND PHA.SEGMENT1 = :PO_ORDER;

DECLARE
   f_line       VARCHAR2 (32000);
   f            UTL_FILE.file_type;
   f_dir        VARCHAR2 (250);
   fname        VARCHAR2 (50);
   Comma1       VARCHAR (10);
   Comma2       VARCHAR (10);
   Comma3       VARCHAR (10);
   Comma4       VARCHAR (10);
   Comma5       VARCHAR (10);
 
BEGIN
   f_dir := '/usr/tmp';
   fname := 'TEST.txt';
   f := UTL_FILE.fopen (f_dir, fname, 'r');

 
   LOOP
      BEGIN
        
          UTL_FILE.get_line (f, f_line);
        EXCEPTION
         WHEN NO_DATA_FOUND
         THEN
            EXIT;
      END;

    
   V_ATTACH := V_ATTACH || CHR(10) ||f_line;
   
   SRW.MESSAGE(10002, V_LONG_TXT);

   ---   DBMS_OUTPUT.put_line(  f_line );

     
   END LOOP;

   UTL_FILE.fclose (f);
   COMMIT;
  
   Return V_ATTACH;
  
END;
end;