Here's the 23rd post highlighting key new features of the upcoming v257 release of systemd. #systemd257
In systemd, as mentioned in one of the previous installments, we are adopting the Varlink IPC at more and more places.
To interface with Varlink IPC from the command line we provide the "varlinkctl" tool. "varlinkctl introspect <socket>" for example introspects which method calls, types, and errors a service provides. Similar, "varlinkctl call <socket> <method> <json>" calls a method.
Here are two examples using that:
varlinkctl introspect /run/systemd/io.systemd.Credentials
and
varlinkctl call /run/systemd/io.systemd.Credentials io.systemd.Credentials.Encrypt '{"text":"foobar"}'
The 2nd argument always specifies the entrypoint socket to talk to. In most cases where you call this locally that's the file system path of an AF_UNIX socket. However this can also be the path to an executable, in which case the executable is invoked and told via $LISTEN_FDNAMES (i.e.
@pid_eins Why two method identifiers? The scheme you mentioned earlier was socket-method-json
@anselmschueler hmm? the /run/systemd/io.systemd.Credentials is an AF_UNIX socket pathin the fs. Maybe you misread that?
@pid_eins Ah. Unfortunate line break placement.