class ftp_data_sender :This engine sends data over a FTP data connection coming from a local sender. The socket must already be open.
esys:Unixqueue.event_system -> mode:transmission_mode -> local_sender:local_sender -> descr:Unix.file_descr -> unit ->
It is ensured that
local_sender is always closed after operation
(whether successful or not). The socket
descr remains open.
method local_sender :