This change makes all the standard library and kernel headers use header
guards with a consistent scheme within the reserved namespace to avoid
conflicts with non-standard-library-implementation code.
This properly avoids problems where the compiler is unaware that this is the
implementation and assumes it can rely on the implementation. For instance,
it might implement calloc using a call to calloc.
Restructure the code that wrongly assumed __STDC_HOSTED__ meant userspace.
I hereby relicense all my work on Sortix under the ISC license as below.
All Sortix contributions by other people are already under this license,
are not substantial enough to be copyrightable, or have been removed.
All imported code from other projects is compatible with this license.
All GPL licensed code from other projects had previously been removed.
Copyright 2011-2016 Jonas 'Sortie' Termansen and contributors.
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