From:	"Duncan Coutts" <Duncan DOT Coutts AT dial DOT pipex DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: DJGPP Support Dual Processor?
Date:	Wed, 22 Sep 1999 23:04:03 +0100
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>This is probably answered in the FAQ somewhere but does DJGPP support
dual
>processor?


DJGPP runs using DPMI which has many nice features such as memory
protection, virtual memory, but it is still Dos single tasking.
Win95+, Unix and other more advanced OSs support multitasking
(pre-emptive, not co-operative) by using multiple threads. Some OS's
(WinNT & probably some Unix versions) can take advantage of multiple
processors by allowing different threads to run on different
processors.

Some languages are specially designed for parallel processing although
this is usually for array processing systems rather than
multithreading designs which fit more easily into traditional
languages. C++ is a traditional language, but there are no features in
the language or in standard libraries for multithreading (as in Java).
Any multitasking is platform specific and therefore non-portable.
Unfortunately for you, DJGPP's platform has no such features.

Some people have implement multithreading in C++ but this is very
difficult and is a major chunk of writing an operating system kernel.

Duncan Coutts.

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