Why are the pseudo-tables arrays of pointers?
The short answer is to save memory. If rta_add_table() were to copy the table definition your application would have the definition two places in memory: internal to RTA, and in your application code. By saving the pointers to the table and column definitions we avoid using lots of memory to duplicate data. Saving pointers has the second advantage of letting you change the table definition on the fly if needed.
