'RELENG_4_0_0_RELEASE'.

This commit was manufactured to restore the state of the 4.0-RELEASE image.
Releases prior to 5.3-RELEASE are omitting the secure/ and crypto/ subdirs.

just use _foo() <-- foo().  In the case of a libpthread that doesn't do
call conversion (such as linuxthreads and our upcoming libpthread), this
is adequate.  In the case of libc_r, we still need three names, which are
now _thread_sys_foo() <-- _foo() <-- foo().

Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(),
nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo().

Remove all internal libc usage of: creat(), pause(), sleep(), system(),
tcdrain(), wait(), and waitpid().

Make thread cancellation fully POSIX-compliant.

Suggested by:	deischen

points.  For library functions, the pattern is __sleep() <--
_libc_sleep() <-- sleep().  The arrows represent weak aliases.  For
system calls, the pattern is _read() <-- _libc_read() <-- read().

where "/var/db/kvm_kernel.db" doesn't exist.

#defines that are compatable with ours).  I made some some minor tweaks
to the leading '_' tests.

Again, this is off by default for the moment.  This probably should be
split into seperate files (like some of our other libc files that could
do with some splitting).

Obtained from: OpenBSD (plus some minor tweaks)

  - Use MAP_FAILED instead of the constant -1 to indicate
    failure (required by POSIX).
  - Removed flag arguments of '0' (required by POSIX).
  - Fixed code which expected an error return of 0.
  - Fixed code which thought any address with the high bit set
    was an error.
  - Check for failure where no checks were present.

Discussed with:	bde

Submitted-By: Kent Vander Velden <graphix@iastate.edu>