radare2/libr/io

RIO design
==========

rio api allows to seamlessly access to underlying IO backends
and define rules on top of it to act as an mmu.

Actions
-------
 - open
 - read
 - seek
 - write
 - close

Layers
------
 - cache    caches write ops and modifies reads
 - map      allows to map a certain file at a given offset
 - sections like maps, but provide more information for virtual addressing

Features
--------
 - undo
 - buffer
 - desc

fn read(io: IO) {
	ut64 offset;
	if io.offset
}