Subject: Detecting ANSI.SYS

87. *****
 Q: How do I find out if the ANSI.SYS driver has been loaded?

 A: The source code of the relevant function is given below.
However, this is not necessarily a good solution. First, it requires
at least MS-DOS version 4.0. Second, there are other, compatible
screen drivers like ZANSI.SYS. You probably are more interested if
such a screen driver has been installed rather than if it is
ANSI.SYS in particular. To find out if any compatible screen driver
is operative use ISANSIFN from TSUNTG.TPU from
 112570 Aug 16 1994 ftp://garbo.uwasa.fi/pc/ts/tspa3470.zip
 tspa3470.zip Turbo Pascal 7.0 real mode units for (real:-) programmers
  uses Dos;
  function ANSIOKFN : boolean;
  var regs : registers;
  begin
    if swap(DosVersion) < $0400 then begin
      writeln ('Error: MS-DOS 4+ required');
      ansiokfn := false;
      halt;
    end;
    FillChar (regs, SizeOf(regs), 0);
    regs.ax := $1A00;
    Intr ($2F, regs);
    ansiokfn := regs.al = $FF;
  end; (* ansiokfn *)
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