Make pdwait(2) cancellable, same as all other wait*(2) syscalls wrappers.
Reviewed by: asomers, markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D54592
Access __libsys_interposing with __libc_interposing_slot() in all
cases to support a move of these wrappers back to libc.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D44239
Long ago (e129c18a83) __sys_sigwait was wrapped to prevent sigwait()
from returning with EINTR. Through a series of changes this wrapper
become __libc_sigwait which was internal to libc and used solely in the
interposing table. To support a move of sigwait back to libc, move this
wrapper into libsys and rename it with an __libsys_ prefix.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D44238
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