Xref: news2.mv.net comp.os.msdos.djgpp:6891
From: Laurentiu Badea <bytemare AT lmn DOT pub DOT ro>
Newsgroups: comp.os.msdos.djgpp
Subject: Win95 and __dpmi_set_segment_limit
Date: Tue, 06 Aug 1996 17:33:06 +0200
Organization: Laboratory for Numerical Methods
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Message-ID: <32076355.38A06A59@lmn.pub.ro>
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CC: bytemare AT lmn DOT pub DOT ro
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

1.
Well, I noticed that __dpmi_set_segment_limit fails for a selector
allocated
using dpmi, if the limit is higher than 1Mb, and you're under W95.
The "reason" for this is that W95 makes the descriptor 16bit,
byte-aligned
which  gives the 1Mb limit since it has only 20bits for limit.
The workaround for it was to __dpmi_get_descriptor, set it to 32bit,
page-
aligned, set the limit (in 4192-byte pages), then __dpmi_set_descriptor.
Has anyone experienced these problems or is my config faulty somehow ?

2.
Doesn't anyone need the dpmi function to release physical->linear
mapping ?
As far as I know, only DPMI1.0+ has this function.
I did once a scan for a linear frame buffer and I quickly ran out of
page
table with cwsdpmi.

3.
How can I free a .dxe, once loaded and used ? The only function in dxe.h
is dxeload or something. And, is the dxe run at the same CPL as my main
prog
or not ? Actually, I want to know if I can do I/O in it or not ( I
remember
I've read somewhere that I shouldn't do I/O in a dxe ).

4.
If I write a real mode int. handler (in asm), how can I use it ?
djgpp (gas) is known to use 32bit assembly so I'd have trouble with
default 
word sizes, on execution. Djasm doesn't know to output .o or .obj.
Do I have to make it .com and load it as a file or there's another way
to do
it ?

5.
make  doesn't understand a single $ as in specs, and instead recognizes 
$^ with (I think) the same meaning.

6.
I wanted to say something about fsdb too, but I forgot. Next time.


Thanks,
Laurentiu

PS. Please email responses too.
-- 
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| Laurentiu Badea,            
bytemare AT lmn DOT pub DOT ro                           |
| CS student at PUB,          
laur AT ulise DOT cs DOT pub DOT ro                          |
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