[Lazarus] The future of desktop

Kostas Michalopoulos badsectoracula at gmail.com
Tue Dec 3 14:16:49 CET 2013


On Mon, Dec 2, 2013 at 9:55 PM, Hans-Peter Diettrich
<DrDiettrich1 at aol.com> wrote:
>
> Right, but it was the first desktop presented by Microsoft.
>

No it wasn't. GEM was presented by Digital Research, Microsoft had
nothing to do with it.

>
> I'm not sure what GEM has to do with multitasking.
>

You said that they were technically similar, which isn't the case.
Multitasking was an example of a major technical difference they had.

>
> I don't see a need for an special Windows compiler. The only requirement is
> a linker that links the resources into the executable. This was a separate
> program for a long time, in addition to the compiler and linker.
>

Windows (Win16) executables are a different format and while a linker
*could* do it, a windows-aware compiler is still needed. The Win16
calling convention is (was) different to whatever DOS compilers used
(usually compilers used their own). Windows was doing software-based
virtual memory management and would unload parts of the program by
unloading functions and patching the memory where the function was
make a system call for loading them back (so running code that tried
to call the function would continue to work). The compiler had to know
about that do make proper prologs and epilogs. Also AFAIK callbacks
required special handling too.

Some notes are given in
http://www.openwatcom.org/index.php/Exploring_Windows_3.x but that is
mostly Win3.x specific. There some notes about Windows 1.0 and Windows
2.0 in Raymond Chen's "the old new thing" blog, but i can't find
specifics right now.




More information about the Lazarus mailing list