One way I’ve seen attachments go out of SAP is using a custom SAP RFC called by a webMethods SAP adapter service.
The adapter service has this output structure in the ‘Request Field Selection’ tab:
BINARY_TAB.LINE (Byte Array)
Since this is autogenerated, the SAP RFC must have a corresponding output signature.
A Flow service calls the adapter service, then runs a LOOP over /BINARY_TAB, with the contents of the LINE element converted & appended within the loop.
#Integration-Server-and-ESB#webMethods#Adapters-and-E-Standards