I get the impression that there might be a way to write to the systemd journal, json data directly without first converting it to the format the sd_journal* functions expect. Is this possible or not?
My suspicion is because of some comments about an inbuilt json parser. However the man pages suggest otherwise.
Also, I note that if your write to stdout in the format
<priority> message
The priority will end up in the PRIORITY="priority" field and message will end up in MESSAGE="message" field. But can other structured field data be input?
Note: The man pages do not talk about the last feature I mention. So I wouldn't be surprised if they are slightly out of date which is why I am asking.