From:	dvldbg AT cs DOT umu DOT se
Subject:	Absolute read
To:	djgpp AT sun DOT soe DOT clarkson DOT edu
Date:	Mon, 3 Feb 92 20:32:29 GMT
Cc:	dvldbg AT cs DOT umu DOT se (Daniel Brahneborg)
Status:	O

I looked at the sources for the function library, trying to
figure out how to do an absolute disk read, but just got
confused. In the source for 'read', EBX, ECX and EDX are set
to the arguments, and then an 'int 21h' is done, with ah=3fh.
But... In the description of that function, CX should be
the number of bytes, and DS:DX the adress to read to. How does
the bios know that is should use EDX instead of just DX?
And what happens if you try to read more than 65535 bytes?

And, what I really want to know, how do I read a specific
sector?

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