🚀 go-pugleaf

Keith Fuller (keithf@Nimitz.mcs.kent.edu) wrote:
: We know that OS/2 runs DOS, Windows and OS/2 applications.
: So my ignorant question is, why write OS/2 applications?  
: What more do you get compared to Windows applications?

1) Programs run faster
   ~~~~~~~~~~~~~~~~~~~
An OS/2 program running natively under OS/2 will run faster than an
equivalent Windows program, because it won't have to go through the
hassle of starting up a DOS box, starting a Windows session,
coordinating seamless windows on an OS/2 desktop, etc.

OS/2 2.0 native applications run faster because they are 32-bit
applications.  This would be equivalent to Windows Enhanced
applications without the hassle of starting a 16-bit DOS and using it
to service all the operating system requests like in Windows now.


2) Programs run better
   ~~~~~~~~~~~~~~~~~~~

In Windows, when you load files from disks, recalculate spreadsheets,
tell a word processor to print, run a word processor in WYSIWYG mode,
etc. you have to wait for the hourglass a lot. This is because Windows
applications cannot multitask within themselves.  Once the program
starts reading a file from the disk, it has to read the entire file
before the rest of the program can continue for example.

OS/2 allows "multi threading".  A single program can multitask
different parts of itself.  For example, you can tell the word
processor to analyse the reading level of your text.  While the whole
document is being analyzed "in the background", you can continue
working on the document.  OS/2 applications don't show the hourglass
(or clock in OS/2's case) nearly as often as Windows.

There are many more OS/2 specific features like this that are not
available to Windows programmers.  Good Windows programmers might be
able to simulate some of these features, but not all of them.


3) OS/2 programs run safer.
   ~~~~~~~~~~~~~~~~~~~~~~
OS/2 is a preemptive multitasking operating system.  This means that
applications have no say in the matter.  On the other hand, windows
programs can easily take over and not let any other programs run.
Just put an hour glass on the screen and go.

There is also very little memory protection in Windows.  A program can
start running, make a mistake, and overwrite memory anywhere in the
system with disasterous results (such as User Application Errors). In
OS/2, this is much more difficult to do "by mistake".

An example of this safety is when an hour glass appears on the screen
in Windows. When an application displays an hour glass in Windows, it
locks up ALL of Windows.  You cannot switch to another application
while the first one is busy.  You have to wait for the first one to
finish.  If it never finishes (because of a problem in the program)
you have to reboot.

In OS/2 however, an application may put a clock on the screen because
it may not want you to change a document while it is being printed for
example. The difference is you can still move the window around, click on
other applications, and run them normally.  The one program doesn't take
over the entire machine.

- Kevin Lowey (Lowey@Sask.USask.CA)
>>>>> Anonymous FTP to FTP.USASK.CA for DOS, OS/2, and Windows programs <<<<<