Standard I/O assumptions

[jalvarez]

Standard I/O in some builds of newlib can be redirected (e.g. to a serial or an ethernet port) by overriding _read_r() and _write_r(). Others require overriding the SWI handler. Were there any assumptions about I/O when newlib was built for devkitARM? e.g. how do you redirect I/O when using a game console?

BTW - Thanks for a reliable and updated GNU toolchain for ARM.