Date   : Fri, 01 Feb 1985 00:02:00 GMT
From   : grayson%uiucuxc.uucp@BRL-TGR.ARPA
Subject: Re: permanently changing default disk fr

>I am running CP/M-86, and want to be able to set the default disk from within
>a program in such a way that it *REMAINS* set after exiting the program.

Just modify the byte at 0004 - half of it contains the default drive number,
and half contains the default user number.  (I forget which half, but that
can easily be discovered by experiment).

       uucp:   {ihnp4,pur-ee}!uiucdcs!uiucuxc!grayson
               Dan Grayson, Math Dept, Univ of Ill, Urbana 61801