`BABELTRACE_COMMON_LOG_LEVEL`::
    Common functions's log level. The available values are the same as
    for the manopt:babeltrace2(1):--log-level option of man:babeltrace2(1).

`BABELTRACE_COMPAT_LOG_LEVEL`::
    Compatibility functions's log level. The available values are the
    same as for the manopt:babeltrace2(1):--log-level option of
    man:babeltrace2(1).

`BABELTRACE_TERM_COLOR`::
    Force the terminal color support. The available values are:
+
--
`AUTO`::
    Only emit terminal color codes when the standard output and error
    streams are connected to a color-capable terminal.

`NEVER`::
    Never emit terminal color codes.

`ALWAYS`::
    Always emit terminal color codes.
--