There is possibility to explicitly acknowledge the receipt of the
encrypted packet, by generating the reply of
contains the packet identifier.
ACK packets can be generated explicitly by
command, or during the tossing procedure if -gen-ack option
General workflow with acknowledgement is following, assuming that Alice has some outbound packets for Bob:
alice$ nncp-xfer -keep -tx -node bob /mnt/shared
bob$ nncp-xfer -rx /mnt/shared
That will also check if copied packets checksum is not mismatched.
bob$ nncp-ack -node alice 4>acks
bob$ nncp-xfer [-keep] -tx /mnt/shared
bob$ nncp-rm -node alice -pkt <acks
alice$ nncp-xfer -rx /mnt/shared alice$ nncp-toss
Each ACK packet will remove kept corresponding outbound packets, because Bob explicitly confirmed their receipt.
If you generate ACK packet during the tossing, then the list of ACK
packets is saved as empty files directly in the spool.
You can remove transferred ACK packets with