Generete output using function modules.

Hi,

can any one help me in this...

SELECT SINGLE changenr FROM cdpos INTO iv_changenr WHERE objectclas = 'EINKBELEG' AND

objectid = wa_ekpo-ebeln AND tabname = 'EKPO' AND tabkey = iv_tabkey AND fname = 'KEY' AND

chngind = 'I'.

IF sy-subrc = 0.

SELECT SINGLE udate FROM cdhdr INTO iv_udate WHERE objectclas = 'EINKBELEG'

AND objectid = wa_ekpo-ebeln AND changenr = iv_changenr.

I want togenerete the above code using this FMs....

CHANGEDOCUMENT_READ_HEADERS' ..and...CHANGEDOCUMENT_READ_POSITIONS'.

Help me in this..

Thanks,

PK