Working with Files on the Presentation Server
Use the following function modules when working with files on the presentation server:
GUI_DOWNLOAD and GUI_UPLOAD.
Class CL_GUI_FRONTEND_SERVICES gives you the relevant information.
The physical names of the files depend on the operating system of the presentation server. You can, however, make your ABAP programs platform-independent by using logical filenames. For further information, refer toUsing Platform-Independent Filenames.