[Coco] format memory (was) Gotek floppy emulator

[Tormod Volden]

On Mon, Feb 15, 2016 at 10:57 PM, Bill Pierce via Coco wrote:
> I use 3.3.0 extensively with a large bootfile on Vcc with /d0-/d3, /h0 (emudsk), /x0-/x8 (yes 8), and /r0 (96k), with CoWin AND CoVDG and full DW4 vport/vprint/vterm support as well as pipes. My Coco 3 is the same but with EmuDsk being replaced by RBSuper IDE drivers. I can format drives with no problem (Coco 3 or VCC), even when I'm running other programs in other windows, but if I run the scripts in the "nitros9/6x09L2/scripts", format will fail. I actually had to make a stripped down boot without all my "extras" to get the scripts to run. I think that problem is the scripts load too much in memory at one time and even most "normal" bootfiles will not have enough system ram. It has nothing to do with "total machine ram" as I run VCC in 6309 with 2 meg, and my Coco3 has 6809 and 1 meg, it's the system ram (64k) that holds the entire system AND a copy of each program (or script) loaded. So the real problem is in the size of the bootfile.

When you run format from a script, the script shell interpreter is
also loaded and consumes extra memory. I don't think it matters how
much commands you have in the script file, because the commands are
run sequentially and die when they are done. Unless there would be
"load" commands of course.

So my next question: When you run a script (start it from your
shellplus command shell), does it fork a new shellplus process to run
the script or does it run in the same shell process? My guess is it
forks a new one. I hope at least it reuses the code segment and only
allocates a new data segment. Of course again, it is the limited
system memory that is the problem here, so is the new shell process
taking up so much system memory?

I agree the size of the bootfile is the real problem, if only 11k is
left after boot. But I would like to understand why it hits the
ceiling with format.

You say above "the system ram (64k) that holds the entire system AND a
copy of each program (or script) loaded". Are you correct about this,
why should the program or script be copied into system RAM?

Regards,
Tormod