[9fans] Bits of Plan 9 I wish were more popular...

["Joel C. Salomon" <joelcsalomon@gmail.com>]

In response to the recent troll invasion:

I've just started work at a CNC router manufacturer, doing control
system programming.  The machine I'm using to test & prototype control
algorithms is Linux with the RTAI real-time patches and I/O card
drivers from the Comedi project.  The way to get a hard-real-time
process?  Build and install a ——ing kernel module!  As regards
communicating with arbitrary I/O cards Comedi isn't completely
useless, merely so painful it should be called Tragedi.

The prototyping machine is completely in my control, so I could use
Plan 9 — if I could justify writing the drivers.  Trouble is, the
driver for the D/A converter comes with Comedi and someone here has
already written a driver for the quadrature encoder.  So I'm stuck on
that end.  I got a lot of programming done in school using acme under
Plan 9; for the first time I realize why the lunix world likes
Eclipse.  ☹

On the production side, I'm about to inherit the code base for the
controller.  Takes instructions from a PC host via USB and fans them
out to separate motion controller units.  And passes information back.
 And tinkers with the data stream when that's called for.  No
operating system.  I miss libthread — I may yet port it for a later
version, if I'm going to be contributing much to the controller rather
than just maintaining it.

One change I probably will make (since the data structures are all
scheduled for radical change) is in the transport.  The current code
base has corresponding structures on different machines declared with
the various "packed" pragmas and transported with byte-order-swapping
— when I get my hands on it it'll be done with proper marshalling.

So there we have it: sane real-time, decent hardware interfaces,
libthread, and data transport methods.  Plan 9 still has plenty to
teach the rest of the computing world.

--Joel