For anyone wondering, this is the component that supports fingerprint readers. I initially thought that systemd had moved printf to a daemon.
Running printf calls in their own isolated and unprivileged process would reduce the severity of some attacks for sure :)
Alternatively, the daemon could run as a networked printf server for fun and profit
That’s because Linux file names are limited to 8 characters (plus a three letter extension).
both the cachefiles dir and error_inject are >8 chars