vomlehn@utexas-11.ARPA@sri-unix.UUCP (08/31/83)
From: vomlehn <vomlehn@utexas-11.ARPA> There are three operating systems that have advantages over the others that I've used. One is the DTSS operating system, which is what I used at college. It is very user friendly, with lots of easily accessable help files and compilers that are not only fast but also tell you what you did wrong in a way that you can understand without ever reading a manual. The design of the OS is different from all others that I've used in that it has the concept of a "current file". This is something that, by default, all of system software manipulates, such as all of the compilers, editors, formatters, etc. It is available only on Honeywell machines and is thus not very portable. Lots of work has gone into this system in order to support a simple and consistent model of what happens when the user does something. One serious deficiency is the lack of a very powerful command language permitting decent command procedures. Command procedures can be nested and have parameter expansion, but don't have any sort of conditional (if-then-else) or looping facilities. The second reasonable OS is UNIX (tm). It's advantages include a fairly extensive documentation system (via man) and the ability to do just about anything you want even if you are a non-privledged user, such as start lots of concurrent tasks and create arbitrarily nested directories. It also has a standard language that permits easy access to all of the facilties. It has problems in that it has a too terse command interface. There are lots of UNIX's, which means that there is lots of software out there, but this can also be a disadvantage because there are lots of inconsistencies in the interfaces of various programs. Command procedures are very flexible but a bit hard to understand. They even support block structured control facilities. The third is VAX/VMS. This system still has an on-line documentation system, but not nearly as extensive as the others. It has a powerful command language which is easy to work with at first but which gets more difficult the more arcane the task you want to accomplish. The command interface is very consistent, which is indispensable for the novice user and almost as important for the more experienced user. The command interface is standard for all modules, permitting easy to understand error messages. VMS is, unfortunately, full of lots of little gotcha's when you are doing systems work, many of which at the same time make life easier for the less experienced user. Which do I like? It depends on what I am doing, none of these have everything I want in the way I want it. I like DTSS but since it requires an expensive Honeywell system, I'd say that VAX/VMS would be my preference for most situation; UNIX is doesn't do as much work for me as I would like.