The device already sends one. There are actually two connections going
on:
server to client - this is the smartcard channel, it reuses the VSC protocol.
server to device - this is an internal connection using VSC too.
We generally just passthrough all messages from the client to the device,
and from the device to the client. We only rewrite the reader_id because
the device knows about a single id (it is actually a card id), and we
may manage more then one in the future.
Bottom line is that there was an extra VSC_Error message reaching the client.
hold_item called on init_send_data, matching release.
This is not the behavior of red_worker - we ref++ (==hold_item) when
sending the item, and --refs when releasing it, instead of only holding
if the send is blocked.
Note 1: Naming: hold_pipe_item is the proc name, the variable is called
hold_item, this is similar to release_item/release_pipe_item naming.
Note 2: All channels have empty implementation, we later use this when
red_worker get's RedChannelized.