NetBSD

From ArticleWorld

NetBSD is an open source BSD Unix-like operating system, forked from 386BSD. NetBSD has a very portable architecture, allowing it to run on a wide range of platforms. It is also highly regarded for its standard compliance, making it a top choice for embedded systems.

Historically, NetBSD has split from 386BSD, as Chris Demetriou, Theo de Raadt, Adam Glass and Charles Hannum felt that the direction taken by the development was wrong. The four developers wanted their system to be as portable as possible, and the first version was released in March 1993, as NetBSD 0.8.

Platforms

NetBSD has such a portable design, that it was ported on more than 50 platforms with more than 17 CPU architectures, and several other ports in development.

What makes its architecture so portable is that the source code is heavily centralized. Any change that is not hardware-specific can be immediately committed among all platforms. The architecture is also designed so that very few parts of the operating system are CPU-dependent. Even the device drivers are usually platform dependent, through a comprehensive and coherent number of abstractions, that enable, for example, the same sound card to be handled by the same driver regardless of the host CPU. This means that the porting process, while not effortless, is greatly simplified, making NetBSD an ideal choice for many new architectures or embedded systems.

Software compatibility

In addition to the great hardware portability, NetBSD also features a highly regarded set of compatibility features.

Many foreign file systems are supported, starting from the usual ext2 and FAT to the less common today, the likes of FileCore (RiscOS) or Amiga's FFS.

The most appreciated compatibility feature of NetBSD is the binary compatibility with other operating systems. It emulates the system calls of a variety of Unix and Unix-like operating systems, allowing it to run native binaries of those operating system. There is even a Windows compatibility module, although it is far from being complete.

pkgsrc

pkgsrc is a repository that includes a large number of packages (source packages). Accompanied by the package manager with the same name, the installation of packages is very easy. Precompiled binaries also exist, and dependencies are automatically resolved.