* * * * *
                                        
                    A twisty passage of Windows, all fragile
                                        
> The HLT instruction tells the CPU (Central Processing Unit) to shut itself
> down until the next hardware interrupt. This is a big win on laptops since
> it reduces power consumption and thereby saves your lap from third-degree
> burns.
> 
> We (well, specifically, Jeff) had this implemented and working in Windows
> 95 but discovered to our dismay that there were many laptops (some from a
> major manufacturer) which would lock up unrecoverably if you issued a HLT
> instruction.
> 
> So we had to back it out.
> 
> Then the aftermarket HLT programs came out and people wrote, “Stupid
> Microsoft. Why did they leave this feature out of Windows.” I had to sit
> quietly while people accused Microsoft of being stupid and/or lazy and/or
> selfish.
> 

“Hardw are Backwards compatibility [1]”

From Mark [2] come a pointer [3] to Raymond Chen's weblog [4], a developer
from Microsoft [5]. An amazing insight into Microsoft development, covering
why they did what they did (The Old New Thing: History) [6], and >why they do
what they do (The Old New Thing: Code) [7].

Even if you aren't a developer for Microsoft Windows, it's still facinating
reading, such as this little bit:

> CreateMenu [8] creates a horizontal menu bar, suitable for attaching to a
> top-level window. This is the sort of menu that says “File, Edit”, and so
> on.
> 
> CreatePopupMenu [9] creates a vertical popup menu, suitable for use as a
> submenu of another menu (either a horizontal menu bar or another popup
> menu) or as the root of a context menu.
> 
> If you get the two confused, you can get strange menu behavior. Windows on
> rare occasions detects that you confused the two converts as appropriate,
> but I wouldn't count on Windows successfully reading your mind.
> 

“What' s the difference between CreateMenu and CreatePopupMenu? [10]”

From reading Raymond's blog, it seems that Microsoft goes to great lengths to
protect mediocre programmers and keep their programs running; their backwards
compatibility legacy is quite impressive (I can still run an editor written
in 1982 under MS (Microsoft)-DOS (Disk Operating System) 1.0 on Windows XP,
some twenty-two years later). With so much legacy code (MS-DOS versions 1.0
(1981) through 7.x (1995) and Windows 1.0 (1985) through Windows XP) it's no
wonder Windows is such a mess, much less that it still runs.

[1] http://weblogs.asp.net/oldnewthing/archive/2003/08/28/54719.aspx
[2] http://grumpy.conman.org/
[3] http://grumpy.conman.org/2004/01/23.1
[4] http://weblogs.asp.net/oldnewthing/
[5] http://www.microsoft.com/
[6] http://weblogs.asp.net/oldnewthing/category/2282.aspx
[7] http://weblogs.asp.net/oldnewthing/category/2281.aspx
[8] http://msdn.microsoft.com/library/en-
[9] http://msdn.microsoft.com/library/en-
[10] http://weblogs.asp.net/oldnewthing/archive/2003/12/30/46594.aspx

Email Sean Conner at sean@conman.org

.