TABLE OF CONTENTS Problems are only opportunities in work clothes.
Henry J. Kaiser
The operating system that we discuss in this book has had a varied and interesting history. Recent history has seen some very interesting developments, culminating with the decision to merge key elements of Tru64 UNIX, such as the Advanced File System (AdvFS) and TruCluster, with the HP-UX kernel to create a powerful new enterprise UNIX. The merger of Compaq Computer Corporation (Compaq) with the Hewlett-Packard Company (HP) is sure to make the future of this product interesting as the two UNIX powerhouses combine resources to create exciting new synergies.
Tru64 UNIX began as an attempt to commercialize the Mach kernel, developed by researchers at Carnegie Mellon University, into the foundation for a new UNIX system. Nothing in the Mach kernel required the UNIX interface, but the researchers saw the benefit of taking a high-performance micro-kernel and providing POSIX operating system services around it. Although UNIX originally began as a small and easily portable system, by this time it had begun to move away from its roots and toward a more monolithic structure. Up to that point, many operating systems were constructed in a monolithic fashion, meaning that all the system's functions were provided from a single, large kernel program; as UNIX began to "grow up" in the late 1980s, it began to exhibit this trend.
A group known as the Open Software Foundation (OSF), making an attempt to reverse this trend, adopted the Mach kernel as...
