OPEN %v_infile%
DELETE format vendor_inv_ext.fil OK
DELETE Vendor_inv_ext OK

Prev_vendor=blanks(25)
First_inv=blanks(15)
Last_inv=blanks(15)

SORT on Vendor Inv_No to temp OPEN

GROUP if prev_vendor<>vendor
EXTRACT prev_vendor first_inv last_inv to Vendor_inv_ext Append if recno()>1 EOF
first_inv=inv_no
last_inv=blanks(15)
prev_vendor=vendor
ELSE
last_inv=inv_no
END

DELETE temp.fil OK
DELETE format temp OK
DELETE last_inv OK
DELETE first_inv OK
DELETE prev_vendor OK