[fpc-devel] Multithreading under DOS

Tomas Hajny XHajT03 at hajny.biz
Thu Sep 26 14:59:26 CEST 2013


On Thu, September 26, 2013 14:45, Michael Schnell wrote:
> On 09/26/2013 02:09 PM, Sven Barth wrote:
>>
>> But on "bare metal" you don't have the OS in your way and thus can of
>> course implement preemptive multithreading as other operating systems
>> are also able to implement preemptive multithreading...
>
> How do you think DOS would "get in the way" ?

Normally because the application using the library needs to use the
operating system services (e.g. I/O functions). As long as we talk about
DOS applications (and DOS RTL), this is done using DOS functions.


> As this is Dos, only a single program runs. Same gaps the interrupts it
> wants to handle (e.g. timer, keyboard  or serial, this in fact is a
> usual way to do DOS programs). Now it runs and DOS sleeps.

...except when it uses just any RTL function...

Tomas





More information about the fpc-devel mailing list