#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
