Lasermoon Linux was the first POSIX certified distro: http://www.ukuug.org/newsletter/linux-newsletter/linux@uk21/posix.shtml http://www.ukuug.org/newsletter/l

Lasermoon Linux was the first POSIX certified distro: http://www.ukuug.org/newsletter/linux-newsletter/linux@uk21/posix.shtml http://www.ukuug.org/newsletter/linux-newsletter/linux@uk21/... For Linux distros they are either too small to be certified, or too large to care for it anymore.