Christopher B. Browne's Home Page

4. GNU Hurd

Official GNU Hurd web page

This was to be the kernel for the "official" FSF/GNU operating system project, the goal being to create a "free" version of Unix. Other "free" OSes such as Linux and FreeBSD have rather beaten Hurd to the punch.

Hurd is an acronym for "Hird of Unix-Replacing Daemons". Hird, in turn, is an acronym for "Hurd of Interfaces Representing Depth".

The original goal of the FSF was to create a free Unix -compatible operating system. For the first several years, they worked on the tools with which to build this OS, namely:

Unfortunately, it wasn't until quite recently that they had had a sufficient base of tools to be able to create an OS kernel. Other projects (Linux, the sundry BSDs ) have provided other free Unix-like operating systems providing people generally more satisfying solutions to their Unix needs.

One brief description of Hurd says that: " The Hurd ... breaks the giant Unix kernel down into various MACH programs running as daemons. Working in concert with facilities placed in the C library, these daemons provide all of the POSIX system-calls and features; from the outside they look just like a standard Unix kernel. This means that, for practical purposes, anything that you can port to Linux will also port to the Hurd. "

The hoped-for advantages of Hurd (over alternatives) were:

Contact me at