Expand the I/O buffer according to the specified io_block_size
Expand the I/O buffer according to the specified io_block_size

This is probably not going to change much, as we're dominated by I/O
reading anyway (especially with ascii). But it does seem more consistent.

mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs