🚀 go-pugleaf

Yes, OS/2 uses  preemptive scheduling

I use CodeView and I only need one display
to debug PM applications.

Ralph Yozzo

In article <16134@rouge.usl.edu> pcb@cacs.usl.edu (Peter C. Bahrs) writes:
>I am totally disgusted with windows 3.0 and sdk programming?
>Why, because my cost for hardware (speed and memory and extra
>monitor) has gone up!  
I think the machine is still cheaper (even with 8MB and debug screen ..)
than a machine that can satifyingly run X11.

>I can say that after 4 years of serious SDK windows programming, I still
>like X (Interviews and Motif) much better because of the feel.
>What is development in the OS2/PM environment like?
Not easier :-), but more fun and more efficiently because you can run
all your tools, editor, compiler simultaneously. To work seriously, you
need 8MB (without LanManager, otherwise 12-16MB) ~100MB disk, 386/25MHz
or better, SuperVGA or 8514 or TIGA.

>Does OS2/PM do preemptive scheduling?  
Yes, dynamic scheduling.

>What is debugging like?
>Do I need a dual display?   
Secondary display is not required but strongly recommended. CodeView.

>How is the OO PM environments like
>Smalltalk, stable?
I don't use them, only plain C at the moment.

>Now that I have the horsepower for doing windows stuff, it occurs to 
>me that I can and may switch to OS2.
If you have the time (and money) you can try it. I like it much better
than DOS/Windows 3.0.

Kai Uwe Rommel

--
/* Kai Uwe Rommel
 * Munich
 * rommel@lan.informatik.tu-muenchen.dbp.de
 */

I've never done any Windows programming, but after writing close to 30,000
lines of C code for OS/2 PM I will say the following things:

The learning curve is EXTREMELY steep initially, because of the forced 
difference in coding style, but once you get over-the-hump, it smooths out
a good bit.

Debugging window procedures is a pain, especially since (up to and including
OS/2 1.2) debuggers which debug PM programs cannot be PM programs themselves,
due to the way PM processes input (and a few other technical issues which I
will not go into here).  So, you are forced to use a text-mode debugger (the
only two I have ever used are CodeView and LogiTech, both of which have their
good and bad points) which is archaic at best.

I have seen some Windows source, and I will say that the OS/2 API's have 
Windows beat by a long shot, unless you are biased towards Unix (and are 
thus accustomed to names like those in Windows.  No flames regarding this
please...).

OS/2 (not PM) does preemptive multitasking, but because PM processes input
in a strange manner (there was once a big discussion regarding whether or
not this was a design flaw, but I don't remember where) you must follow
certain rules, or you are going to experience hangups in the input data
stream (and since a lot of things are based on input, the system appears
to freeze.  A good example of this is changing the window focus.  If one
program grabs the input queue and doesn't get back to it's polling loop
before the focus is changed, you don't notice the change until it does.).

I hope this helps a bit...Feel free to send me EMAIL offline if you wish to
discuss this further...

Cheers,
Q

>/ otter:comp.os.os2.programmer / pcb@cacs.usl.edu (Peter C. Bahrs) /  4:10 am  Oct  9, 1990 /
>I am totally disgusted with windows 3.0 and sdk programming?
>Why, because my cost for hardware (speed and memory and extra
>monitor) has gone up!  
>
>I can say that after 4 years of serious SDK windows programming, I still
>like X (Interviews and Motif) much better because of the feel.
>What is development in the OS2/PM environment like?
>
>Does OS2/PM do preemptive scheduling?  What is debugging like?
>Do I need a dual display?   How is the OO PM environments like
>Smalltalk, stable?
>
>Now that I have the horsepower for doing windows stuff, it occurs to 
>me that I can and may switch to OS2.
>
I havent't programmed in windows but i've done a quite a bit of 
programming and reading up
on PM and will say the following things
1) OS/2 PM does premptive scheduling
2) Debugging a PM applicationb is quite painful because since a whole 
lot of messages
are kept in a system wide queue wand the fetching of the messages is serialised. SO if any of 
application for whihc the message is intended is not able to do so, it will
choke up the whole OS/2 machine ?? Yum. THings like exchanging window focus and
retreiving timer messages should be taken care of immediately for the 
same reason as above.
3) Having a dual display woulld help in running the debugger in a separate window
however that wouldnot alleviate the message queue problem.

Otherwise i should say that the PM is a pleasure to work with !!

Cheers 
ANUPAM SAHAI