The nng_aio_set_iov() function sets a scatter/gather vector iov on the handle aio.
The iov is a pointer to an array of niov nng_iov structures, which have the following definition:
typedef struct nng_iov {
void * iov_buf;
size_t iov_len;
};
The iov is copied into storage in the aio itself, so that callers may use stack allocated nng_iov
structures. The values pointed to by the iov_buf members are not copied by this function though.
A maximum of four (4) nng_iov members may be supplied.
Note
Earlier versions of the library could accept longer scatter-gather lists. However, no known consumers
have ever needed a scatter-gather list longer than 4 vectors. As a result, the implementation limit
was reduced, and heap allocations which could fail were removed.