The tracer is designed to send the metrics towards a telegraf server
using this kind of configuration:

    [[inputs.socket_listener]]
    service_address = "tcp://localhost:8094"

The telegraf server can then forward the metrics towards an influxdb
server for monitoring or directly to grafana live server[^1] for
introspection.

The influxdb database can also be used to query the metrics after
they've been indexed.

The application using the tracer can use the VLC_TELEGRAF_ENDPOINT
environment variable (eg. VLC_TELEGRAF_ENDPOINT=tcp://127.0.0.1:8094)
to set where the tracer will output the traces to.

A bunch of notes and improvement left for later:

 - Unsafe code is still used for accessing the fields data since an
   union is used and union access is unsafe. It could probably be
   wrapped from the binding implementation.

 - There is no way to specify the address using the configuration
   since vlc_variable is not bound to the Rust bindings and no
   unsafe extern "C" code...