+/**
+ * Buffer usage conditions allows an action to be taken whenever a channel's
+ * buffer usage crosses a set threshold.
+ *
+ * These conditions are periodically evaluated against the current buffer
+ * usage statistics. The period at which these conditions are evaluated is
+ * governed by the channels' monitor timer.
+ *
+ * Note that the use of these conditons does not imply any hysteresis-loop
+ * mechanism. For instance, an upper-bound buffer usage condition set to 75%
+ * will fire everytime the buffer usage goes from a value < 75% to a value that
+ * is >= 75%. The evaluation result does not depend on any lower-bound condition
+ * being reached before the condition is evaluated to true again.
+ *
+ * Buffer usage conditions have the following properties:
+ * - the exact name of the session in which the channel to be monitored is
+ * defined,
+ * - the domain of the channel to be monitored,
+ * - the exact name of the channel to be monitored,
+ * - a usage threshold, expressed either in bytes or as a fraction of total
+ * buffer capacity.
+ *
+ * Wildcards, regular expressions or other globbing mechanisms are not supported
+ * in buffer usage condition properties.
+ */
+
+/*
+ * Create a newly allocated lower-bound buffer usage condition.
+ *
+ * A lower-bound buffer usage condition evaluates to true whenever
+ * a buffer's usage _crosses_ the bound that is defined as part of the
+ * condition's properties from high to low. In other words, the condition only
+ * evaluates to true when a buffer's usage transitions from a value higher than
+ * the threshold defined in the condition to a value lower than the threshold
+ * defined in the condition.
+ *
+ * Returns a new condition on success, NULL on failure. This condition must be
+ * destroyed using lttng_condition_destroy().
+ */