Re: [9fans] What are you using Plan 9 for?

["Ethan A. Gardener" <eekee57@fastmail.fm>]

On Mon, Jun 11, 2018, at 7:14 AM, 刘宇宝 wrote:
> this makes me wondering 
> whether anybody still seriously uses(or used?) Plan 9 for serious work, 
> what software they frequently use, what software is most lack of.

For many years I used it and especially Acme to try to organise my life, including every area of interest I had. Plan 9 and Acme played their parts quite well. I even had multiple Acme sessions running, each with its own plumber. Some windows held sub-instances of Rio, again with their own plumber instances, for projects requiring graphics or PDFs. 

Another use I had for it was playing MUDs, MUSHes, MU* -- telnet-based multi-player games. I particularly liked Rio's "noscroll" feature in this case, as I could catch up with all the messages at my own pace. In fact, I very much like noscroll in general. On the other hand, the lack of color meant I could miss things sometimes, such as a clue in a room description or a private message while travelling -- noscroll isn't really feasible when you're following someone rapidly through a dozen rooms, each with their own description. I never got around to filtering different kinds of messages into different windows. I should have.

Overall, I asked Plan 9 to do quite a lot of things it wasn't really designed for, without writing a bit of C code, and for the most part it proved remarkably convenient. Frustration eventually built up over some things, particularly all the string manipulation -- converting data between the different programs' needs -- when, even after all these years of practice, I am _still_ bad at regular expressions! I developed ideas about another operating system with structured pipes, but around this time I learned to relax. I dropped most of my projects, stopped trying to play so many games so hard, and no longer needed Plan 9 to help me organize it all.

Ironically perhaps, relaxing has freed my creativity so that I'm now programming more than at any time since before I started using Plan 9 full time. Most of it is going into game scripting at the moment, but on the back burner is a Forth-based project; a sort of operating system where the primary interface to all tasks is a Forth interpreter. So far, I've written the basics of a text editor. It's *very* little code! Plan 9 is a very expressive system for how little code it has, but this seems to be a major step beyond that. It's a bit too early to really tell. 

It offers the full power of a systems programming language at the editor prompt. If that sounds like a problem, it's not yet. If it ever becomes a problem for common tasks, I can write safer, higher-level, and probably more convenient words (=functions, =commands,) to handle those tasks. That's arguably how the text editor's basics already work. For instance, change-dotlen performs safety checks before calling the (dangerous, powerful,) move word to adjust the contents of the buffer for inserted or deleted text. rdot ("replace dot") is a user command which calls change-dotlen to do most of the work, then calls move again to copy the string into the buffer. change-dotlen is well tested, rdot is so simple there are obviously no faults. :) (That's not something I really believe in, I tested it too.) None of the other user commands call move, they adjust dot and then call rdot. Adjusting dot means a call to dot! (dot-store), which also has safety checks.

When all the necessary tools are written, there's just no need to use the unsafe features, but neither is there a need to partition those features off into compiled program space. There's no need to learn five different languages for one task, and if you want to point out that a Forth system may well include lots of mini-languages, there's no need for the mini-languages to have -- or LACK -- their own loops, conditionals, variables, or function definitions, not to mention jammed-into-a-string terse syntaxes.

I'd better stop here because I'm getting enthusiastic. :) It is early days yet, I may have to retract some of my beliefs in the future. I still have a Plan 9 system which is almost always on, but now I no longer have a desk of the right proportions to make mouse use comfortable, and can no longer bend over a laptop for hours on end, (a Thinkpad with 3 buttons,) text editing in Plan 9 has become unpleasant. I could patch Samterm and Rio to make it more comfortable, but it's not worth it. 

-- 
The lyf so short, the craft so long to lerne. -- Chaucer