LCDd can send messages back to the client. These messages can be directly related to the last command, or generated for some other reason. Because messages can be generated at any moment, the client should read from the connection at regular intervals. A very simple client could simply ignore all received messages. Not reading the messages will cause trouble !
success
This is the reponse to a command in case everything went ok.
huh?
error_description
This is the response to a command in case something has gone wrong. The description is not meant to be parsed, it's only meant for the programmer of the client. It might be that your command has only been partially executed, for example if you try to reserve 3 keys, and one fails. Your client might need to undo its actions completely.
listen
screen_id
ignore
screen_id
The screen with the screen_id
given is now
visible on the display (listen
) or it is not visible
anymore on the display (ignore
).
key
key
This message will be sent if there was a keypress that should be delivered to the current client.
menuevent
event_type
id
[value
]
The user did something with a client supplied menu. The type of event can be:
select
(action)
The item was activated.
update
(checkbox, ring, numeric, alpha)
The item was modified by the user, so LCDd sends an updated
value
.
plus
(slider)
,
minus
(slider)
The slider was moved to left (minus
)
or right (plus
), so
LCDd sends an updated value
.
enter
This item has been entered, which means it is currently active on the screen. The client could now for example update the value of the item. If it is a menu, it may be needed to update the values of the items in it too, because they may be visible too.
leave
This item has been left, so it is currenly not the (main) active item anymore.
Multiple messages may be generated by one action of the user.