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From:	"arizvi" <ahmadwaris AT hotmail DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	dosmemput and dosmemget
Date:	3 Mar 2005 09:48:47 -0800
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Hi,

I have a question about the behavior of dosmemput and dosmemget.
I am not familiar about the relationship between conventional memory
and dos memory, hence the doubt. The following is a description of
dosmemput from the C Library Reference:

#include <sys/movedata.h>
void dosmemput(const void *buffer, int length, int offset);

Description
This function transfers data from the program's virtual address space
to MS-DOS's conventional memory space.

My doubt it whether the function actually copies data from one memory
space to another, or if there is no actual copying but some sort of
remapping of address spaces. By remapping, I mean something like .. DOS
is told - hey, you have new data at such and such physical memory
location.

I'm sorry if this sounds like a simple question, but as I said - I'm
not familiar with how memory is laid out.

I am writing a program with lots of dosmemput(s) and dosmemget(s).
If I could reduce the number of these function calls by once and for
all telling DOS that I would like to work in DOS memory - there would
be no need for those calls.

I hope this makes sense.

Thanks, 
Ahmad

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