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>5.2. DOS and Windows</H1
><P
>Most DOS extenders come with some interface to DOS services.
Read their docs about that,
but often, they just simulate <TT
CLASS="FUNCTION"
>int 0x21</TT
> and such,
so you do "as if" you are in real mode
(I doubt they have more than stubs
and extend things to work with 32-bit operands;
they most likely will just reflect the interrupt
into the real-mode or vm86 handler).</P
><P
>Docs about DPMI (and much more) can be found on
<A
HREF="ftp://x2ftp.oulu.fi/pub/msdos/programming/"
TARGET="_top"
>ftp://x2ftp.oulu.fi/pub/msdos/programming/</A
>
(again, the original x2ftp site is closing (no more?), so use a
<A
HREF="ftp://ftp.lip6.fr/pub/pc/x2ftp/README.mirror_sites"
TARGET="_top"
>mirror site</A
>).</P
><P
>DJGPP comes with its own (limited)
<SPAN
CLASS="APPLICATION"
>glibc</SPAN
> derivative/subset/replacement, too.</P
><P
>It is possible to cross-compile from Linux to DOS,
see the <TT
CLASS="FILENAME"
>devel/msdos/</TT
> directory
of your local FTP mirror for metalab.unc.edu;
Also see the MOSS DOS-extender from the
<A
HREF="http://www.cs.utah.edu/projects/flux/"
TARGET="_top"
>Flux project</A
>
from the university of Utah.</P
><P
>Other documents and FAQs are more DOS-centered;
we do not recommend DOS development.</P
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><B
>Windows and Co. </B
>This document is not about Windows programming,
you can find lots of documents about it everywhere...
The thing you should know is that there is the
<A
HREF="http://www.cygwin.com"
TARGET="_top"
>cygwin32.dll library</A
>,
for GNU programs to run on Win32 platform; thus, you can use GCC, GAS,
all the GNU tools, and many other Unix applications.</P
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