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Re: command history in dos - how?

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Jim Leonard  <mobygamer@gmail.com> wrote:
>An interesting bit is int 21h ax=440ch which is a "generic character
>device request" which I've never seen before and don't know what it does:
>
>mov     ax, 440Ch
>mov     bx, 2
>mov     cx, 37Fh
>mov     dx, 1AFh
>int     21h             ; DOS - 2+ - IOCTL -

It's querying the the display information (CL=7Fh) of the CON device
(CH=03h) attached to standard error (BX=2). My guess its to find the
screen dimensions, but you'd have to check to see what it does with the
buffer at DS:DX (Table 01552 in my copy of Ralf Brown's Interrupt List).

					Ross Ridge

-- 
 l/  //	  Ross Ridge -- The Great HTMU
[oo][oo]  rridge@csclub.uwaterloo.ca
-()-/()/  http://www.csclub.uwaterloo.ca/~rridge/ 
 db  //	  

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command history in dos - how? Thomas Jensen <lianergoist@sejlgarnet.dk> - 2011-11-02 13:50 +0000
  Re: command history in dos - how? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2011-11-02 10:54 -0400
    Re: command history in dos - how? Thomas Jensen <lianergoist@sejlgarnet.dk> - 2011-11-02 18:56 +0000
      Re: command history in dos - how? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2011-11-02 16:21 -0400
  Re: command history in dos - how? Jim Leonard <mobygamer@gmail.com> - 2011-11-02 08:28 -0700
    Re: command history in dos - how? Thomas Jensen <lianergoist@sejlgarnet.dk> - 2011-11-02 19:03 +0000
    Re: command history in dos - how? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2011-11-02 16:31 -0400
  Re: command history in dos - how? Rugxulo <rugxulo@gmail.com> - 2011-11-02 12:38 -0700

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