The behaviour of plugin_write with regards to fam being NULL has not changed
with the switch to one thread per write plugin, so the documentation should
not change as well.
* ARGUMENTS
* plugin Name of the plugin. If NULL, the value is sent to all registered
* write functions.
- * fam The actual metric family to be processed.
+ * fam The actual metric family to be processed. Must not be NULL.
*
* RETURN VALUE
* Returns zero if the metric family was sucessfully enqueued or non-zero if