*
* If LTTNG_UST_COMPAT_API_VERSION is undefined, API compatibility for
* all API versions is provided.
* If LTTNG_UST_COMPAT_API_VERSION is defined to N, API compatibility
*
* If LTTNG_UST_COMPAT_API_VERSION is undefined, API compatibility for
* all API versions is provided.
* If LTTNG_UST_COMPAT_API_VERSION is defined to N, API compatibility