I've been looking for a while now, I can't find the library or the commands that read and write files from the front SD slot on the wii, can anyone help me out?
if your using libogc, libfat handles all this. You can just use fopen, fread file system commands. This is the quickest way to write any SD code on the Wii.
SD communication is done through IPC sending commands to the IOS (starlet) here is a list of commands
http://www.wiibrew.org/wiki//dev/sdio/slot0 (http://www.wiibrew.org/wiki//dev/sdio/slot0)
you don't really need to understand any of this though if you use libogc as its all layer upon layer that does it all for you.
here is my ocarina code, its very simple as you can see
http://www.pastie.org/private/uagn7dhuywhhh4lzpqblq (http://www.pastie.org/private/uagn7dhuywhhh4lzpqblq)
if you need any further help let me know
thank you very much, thats all I needed. I knew it was libfat but I just couldn't find a reference for all its commands etc