Re: Need UNIX clarification

From: Larry Kilgallen (Kilgallen_at_SpamCop.net)
Date: 01/04/05 

Date: 4 Jan 2005 08:30:47 -0600

In article <Dz$09QlGW2Mu@eisner.encompasserve.org>, clubley@remove_me.eisner.decus.org-Earth.UFP (Simon Clubley) writes:
> In article <8_vCd.16752$P%3.1048216@news20.bellglobal.com>, "Neil Rieck" <n.rieck@sympatico.ca> writes:
>> Believe it or not, I'm more confused than before. Between "public responses
>> in this newsgroup" and "private emails":
>>
>> ~50% said UNIX supported threads but its own kernel was single threaded
>> ~50% said UNIX kernels were multi-threaded.
>>
>
> A clarification from you may be required. :-)
>
> When you are asking about multi-threading capabilities, are you using the
> phrase "multi-threaded" as an alias for multitasking (between different
> processes) or are you using "multi-threaded" in it's current modern form,
> where it describes multiple threads of execution within a single process
> space (and is different from multitasking) ?
>
> IE: VMS has been multitasking from day 1, but was not multi-threaded until
> later.

ASTs have made individual VMS processes multi-threaded from day 1,
but not with the familiar (to some) Unix programming model.

Only after the addition of that Unix programming model was support
added for a single process actually executing on multiple CPUs at
the same time, but that is not the definition of multi-threaded.