RFC_RC 
The structure
Syntax
enum RFC_RC {RFC_OK,
RFC_FAILURE,
RFC_EXCEPTION,
RFC_SYS_EXCEPTION,
RFC_CALL,
RFC_INTERNAL_COM,
RFC_CLOSED,
RFC_RETRY,
RFC_NO_TID,
RFC_EXECUTED,
RFC_SYNCHRONIZE,
RFC_MEMORY_INSUFFICIENT,
RFC_VERSION_MISMATCH,
RFC_NOT_FOUND,
RFC_CALL_NOT_SUPPORTED
};
provides RFC return codes.
This structure is defined in SAPRFC.H.
RFC_OK
ok
RFC_FAILURE
error occurred
RFC_EXCEPTION
exception raised
RFC_SYS_EXCEPTION
system exception raised, connection closed
RFC_CALL
call received
RFC_INTERNAL_COM
internal communication, repeat (internal use only)
RFC_CLOSED
connection closed by the other side
RFC_RETRY
no data yet (RfcListen only)
RFC_NO_TID
no transaction-ID available
RFC_EXECUTED
function already executed
RFC_SYNCHRONIZE
synchronous call in progress (only for Windows)
RFC_MEMORY_INSUFFICIENT
memory insufficient
RFC_VERSION_MISMATCH
version mismatch
RFC_NOT_FOUND
function not found (internal use only)
RFC_CALL_NOT_SUPPORTED
call is not supported on Windows