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See Talk:HP_BASIC_for_OpenVMS#BASIC-PLUS for merge discussion.

Command shell?[edit]

Someone just added the category "Command shells" to BASIC+. I'm not sure I agree.

While it is true that BASIC+ appeared to be a shell to the naive user, it was only processing those commands that were specific to the BASIC+ language, so "OLD", "NEW", "RUN", "SAVE", "COMPILE", and such-like. Other apparent commands that BASIC+ did not itself understand were kicked out to a system service that attempted to match the user's command to one of the known CCL (Concise Command Language) commands that had been defined on that particular system. (NB: I may have the processing order reversed: CCL may have had first-crack at the commands.)

So is BASIC+ really a Command Shell? Or is it just acting as a front-end to the CCL code which would be considered the real Command Shell?

Atlant 13:05, 14 August 2006 (UTC)

That's true, but how is that different from Unix shells? Things like DCL that thoroughly chewed everything you fed it are the exception. Paul Koning 11:01, 30 July 2007 (UTC)
Also BASIC+ was not just an interpreter, it was a KBM (keyboard monitor). This meant that upon entry it HAD to determine if the system was just starting up, had crashed, if you were logged in or out, pass control to $INIT.* or $LOGIN.* (wildcarded because we never know WHO might be the Default KBM in the list of run-time-systems) before ever giving you a prompt. Trap Handlers, Pseudo Keyboards, raising and lowering privledge and calculating how much memory we need to load a file is all done by the KBM (running in User mode). After a command is entered, THEN .CCL is called (every time) before local commands are considered (that was the standard with most KBM's). This is why you never created CCL's with the names new, old or print (try it). The CCL's (Concise Command Lanugage) commands were a unique animal but really nothing more than a list of commands that could be run, stored in dynamic memory (FIP buffering). For most people (including myself), you wouldn't really think of BASIC+ as a command shell. But by comparison, Unix shells are much easier to write than KBM's. Bbump 03:05, 13 August 2007 (UTC)
Small computers, like the Tandy 100 (a laptop with 24K of ram), used basic both as a script language and as a command intepreter. You could run programs from here, including programs encoded in machine code. It really does not matter what command processor you use, in the end, it is the underlying OS (even in DOS), which loads the program. --Wendy.krieger 09:06, 28 October 2007 (UTC)


While DEC took over BASIC-PLUS development, original development was done by EG&H (Evans, Griffiths and Hart). Paul Koning 11:01, 30 July 2007 (UTC)