From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stuart Axon <appg18@dsl.pipex.com>
Subject: How dosemu redirection works?
Date: 21 Jan 2003 06:56:05 +0000
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with dosdbg dD (Dos, disk) turned on I do 
c:\> cd .. 
in the boot.log I see:


INT21 (0) at 9001:1d98: AX=3b00, BX=096e, CX=0000, DX=096e, DS=0b74,
ES=9001
INT2F at 019a:846f: AX=1123, BX=0006, CX=0000, DX=096e, DS=0b74, ES=0100
MFS: Entering dos_fs_redirect, FN=23
MFS: selecting drive fn=23 sda_cds=0x1301f
MFS: FNX=..
MFS: selected drive 2: /home/stuaxo/.dosemu/dosemu/freedos/
MFS: Finished dos_fs_redirect

The int21, ax = 3B would be the change directory command; and the int2f
is the network redirector (eventually leading to mfs.c)

What I can't seem to work out is where the int21 calls the int2f (I
wouldve assumed somewhere in int.c?), or is there a basic mechanism I'm
missing?