WFL/DCP SPO

Current state of Smalltalk platforms

• Squeak6.0 Desktop

  This is the current level used by the DGUI Project which will load in a current Squeak 6 with Squot from the source Squit repo. Desktop is the reference SPO environment, the web version is a convenience for DCMS users. Since the desktop version can run in a desktop sharing session in a browser, or from an MCP node via vnc, it is the preferred version there too.

    WEBSPO is set as the home panel for DCMS devops users.
• The SqueakJS SPO subset (WEBSPO) runs in browsers from images on a browser disk.

On fileIn, a SPO level presumes a level of squeakmap, monticello, etc. but thereafter generally diverges in its internal squit repo. Whether in a browser or on a desktop a SPO must be served from a node of a MCP for the full set of ops.

4720 Story

My first professional Smalltalk use was in 1985/6 and the last big app before the DGUI was in the mid nineties. SPO was/is a term for the system operator console in Burroughs/Unisys MCP. Similarly WFL is Work Flow Language, the MCP Job Control Language and a future intent for the domain space Master Control Program. DCP is domain control program which is novel to domain space.

		The SPO would be associated with a particular Operator Display Terminal (ODT), by assignment in the NDL (Network Definition Language) sources for the machine controlled. The TD series (classic TD830 shown) were typically used in the seventies and early eighties. The "dumb" terminal is actually in the keyboard. I also used an "SR" station type with a more programmable microprocessor introduced after the TD.
This image shows a lot of reverse video, they were normally white text on black. I believe they also could be configured like a contemporary IBM 3270 for "greenscreen" green on black or amber. There also was an ET series (shown below), a more modern version of the TD monitor (shown above, an 800 I believe). My desk had an SR model iirc, unlike these two.

Linux, Mac, or Windows desktop is reference version (DGUI) Desktop and web SPO loaders are available from your DCMS account.

In my reimagined context, SPO is just the smalltalk code which is developed to run in Squeak 5.3 or later from desktop or web in support of domain space.

• MCP console (Unisys, conceptual inspiration).
• FileList proven/adapted for MCP file system model
• CommandShell adapted for mcpcms.
• DCP Console / KEE SPA, morphic is reference version (redvant version linked).

"DGUI" could be somewhat misleading, since here "domain" refers only to the GUI aspect of domain space as such. In fact. anything that could run on a node could produce a native GUI or web UI. The Domains GUI prefers Smalltalk on aesthetic as well as practical grounds but redvant is also used and many embedded systems have their own none of which are what is meant by 'DGUI' in the narrow sense of this page.

"Supervisory Print Out"

In the original MCP based systems one or more consoles could function as the "SPO", the system operator interface. Originally it stood for "Supervisory Print Out" in the early MCP (presumably B5000 or possibly earlier). The ATTACHSPOQ DCALGOL function determines the current SPO.

In my homage it has become simply "SPO" ('spoh') for DCP/MCP, the set of squeak sources as described above as a UI for the dominion control program in the style of the Burroughs MCP. BTW, this is a good place to point out the diff between "Burroughs MCP", "Unisys MCP", and just "MCP". The second is the product marketed by Unisys which until recently I had not had hands on since my use of it as systems programmer in the 80s but which is now available as "MCP Express" that runs under Windows. The last is my invention which is no more than inspired by Burroughs MCP 4, the version of the Algol OS with which I had paid experience than 18/19 the current one in 2020/4718.

Links

• Burroughs Large Systems (external)
• Burroughs MCP Architecture (internal)
• CANDE
• Squeak
• WFL