The function module RSPO_DOWNLOAD_SPOOLJOB can be used for downloading the spool to the local file. You need to pass the spool request number to the function module.
Please note that this function module fits only for the ABAP lists, and not for the spool with images.
PARAMETERS: * Spool Request number p_spool LIKE tsp01-rqident, * File name and the location to store p_file LIKE rlgrap-filename.
CALL FUNCTION 'RSPO_DOWNLOAD_SPOOLJOB' EXPORTING id = p_spool fname = p_file.