ap_append_arrays — concatenate two arrays into a new array
array_header *ap_append_arrays(pool *p, const array_header *first, const array_header *second)
Creates a new array consisting of the elements of
second appended to the elements of
first. If second is empty, the
new array shares memory with first until a new
element is appended. (This is a consequence of using
ap_copy_array_hdr() to create the new array; see
the warning in that function.) Returns a pointer to the new array.