These provide standard APIs, but are implemented using another system
call (e.g., pipe implemented in terms of pipe2) or are interposed by the
threading library to support cancelation.
After discussion with kib (see D44111), I've concluded that it is
better to keep most public interfaces in libc with as little
as possible in libsys.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D44241
Historically we exposed _getlogin as a private symbol on a per-arch basis
(except on aarch64 and riscv) for no obvious reason. We now need to
expose it for libc's use so remove the special case from
makesyscalls.lua and expose it in the generated syscalls.map.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D44116
libc/<arch>/sys/Makefile.inc -> libsys/<arch>/Makefile.sys.
Require that libsys/<arch>/Makefile.sys exist. At least for current
archtiectures, it's not possible for an architecture to not have and MD
syscall bits.
powerpcspe/Makefile.sys's structure means it had to be modified when moved
so rename detection won't work, but it has trivial contents so the
history is unimportant.
Reviewed by: kib, emaste, imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/908
Remove core system call implementations and documentation to lib/libsys
and lib/libsys/<arch> from lib/libc/sys and lib/libc/<arch>/<sys>.
Update paths to allow libc to find them in their new home.
Reviewed by: kib, emaste, imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/908
