FS is for nubz, do these instead:

Read

dd if=/dev/sda of=/dev/stdout

Write

dd if=/dev/stdin of=/dev/sda

Nope, rust is ideal for kernel code, it really is an improvement.

Writing kernel in C is like building a house with a hammer on loosen handle, there is too much give and the builder has to tap it a few times before every strike. You could say the builder knows how to build and secure a house, but hes still a human. The loosen handle adds too much difficulty result in errors which would otherwise be avoided.