OPERATING-SYSTEMS(7)   Miscellaneous Information Manual   OPERATING-SYSTEMS(7)

NAME
     Operating systems – criteria

DESCRIPTION
     Sometimes in conversation I use the term “real operating system” which
     people, perhaps rightfully, take as inflammatory.  But I have actually
     thought about what I mean when I say “real operating system” and come up
     with this list of criteria.

     An operating system should be...

     •   Consistent and cohesive: all parts of the system should have similar
         usage, configuration, documentation and so on.  Parts of the system
         should naturally work together, because they were designed to do so.

     •   Documented: the system should include its own documentation.  A user
         should not have to search some external wiki to learn how the system
         works.  It should be obvious where to find documentation on a
         particular topic.

     •   Programmable: the system should provide a way to program the
         computer.  A computer which cannot be programmed is not a computer at
         all.  Usually this takes the form of a C compiler and the tools that
         go with it.  In earlier times, it might have been a BASIC
         interpreter.

     •   Examinable and modifiable: the full source tree for the system should
         be included, or easily obtainable through official means.  A user
         should have no trouble finding the corresponding source for a part of
         the system.  Together with the previous point, the source tree should
         be compiled by the included toolchain, allowing local modification.

     Some things that may be parts of real operating systems, but are not
     themselves operating systems: a kernel, a package manager, a collection
     of packages.

     I will leave it as an “exercise for the reader” to guess which operating
     systems meet these criteria and which don't.

AUTHORS
     june <june@causal.agency>

Causal Agency                  February 22, 2021                 Causal Agency