errno

ISO C90: errno is defined as macro or lvalue in errno.h
ISO C99: errno is lvalue defined in errno.h
DragonFly uses Thread Locale Storage, C99 Addendum
4.3BSD had no "extern int errno"
old sources often define it manually, even some new code (Gnome, KDE, ...)
normal DragonFly: errno macro -> *__error -> *&errno variable
bandaid for programs which do include errno.h
will be removed in the future
no attempt on compatibility is made on my build machine
find and fix all cases, creates consistency
fix cases where errno.h is not used at all
ld from binutils 2.15 segfaults here
on DragonFly sys/errno.h and errno.h are identical, NetBSD detects those abuses