o main returns int not void
o use return 0 at end of main when needed
o use braces to avoid potentially ambiguous else
o don't default to type int
o #ifdef 0 -> #if 0
Reviewed by: obrien and chuckr
- 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
