You cannot choose your battlefield, God does that for you; but you can plant a standard where a standard never flew.
Figure 15-1 shows the history and genealogy of the systems I examine. All four systems started their independent life in 1991–1993. At that time affordable microprocessor-based computers that supported a 32-bit address space and memory management led to the Cambrian explosion for modern operating systems. Two of the systems, FreeBSD and OpenSolaris, share common ancestry that goes back to the 1978 1BSD version of Unix. FreeBSD is based on BSD/Net2, a distribution of the Berkeley Unix source code that was purged from proprietary AT&T code. Consequently, whereas both FreeBSD and OpenSolaris contain code written at Berkeley, only OpenSolaris contains AT&T code. Specifically, the code behind OpenSolaris traces its origins back to the 1973 version of Unix, which was the first written in C [Salus 1994] (page 54 in the reference). In 2005, Sun released most of the Solaris source code under an open source license.
Linux was developed from scratch in an effort to build a more feature-rich version of Tanenbaum’s teaching-oriented, POSIX-compatible Minix operating system [Tanenbaum 1987]. Thus, though Linux borrowed ideas from both Minix and Unix, it did not derive from their code [Torvalds and Diamond 2001].
The intellectual roots of Windows NT go back to DEC’s VMS through the common involvement of the lead engineer David Cutler in both projects. ...