Contributor: ARNE DE.BRUIJN
{
Small program to demostrate redirection of TP's Output variable
Arne de Bruijn, 1994, PD
}
Unit SmallCrt;
interface
procedure AssignCrt(var F:text);
implementation
uses Dos; {For TextRec, fmClosed, fmOutput}
function InOutCrtOut(var F:text):byte; far; assembler;
asm
cld { Count forwards }
mov dx,ds { Save DS }
lds si,F { Get address of F }
mov cx,[si].TextRec.BufPos { Get number of bytes to write }
lds si,[si].TextRec.BufPtr { Get address of buffer }
@OutChars:
lodsb { Load character to output in AL, and }
{ set SI to next character }
int 29h { Output AL with DOS undocumented fast write }
loop @OutChars { Do all characters (dec(cx); until cx=0) }
mov ds,dx { Restore DS }
end;
function CloseCrtOut(var F:text):byte; far;
begin
TextRec(F).Mode:=fmClosed;
CloseCrtOut:=0;
end;
function OpenCrtOut(var F:text):byte; far;
begin
with TextRec(F) do
begin
Mode:=fmOutput;
BufPos:=0; BufEnd:=0;
InOutFunc:=@InOutCrtOut;
FlushFunc:=@InOutCrtOut;
CloseFunc:=@CloseCrtOut;
end;
OpenCrtOut:=0;
end;
procedure AssignCrt(var F:text);
begin
with TextRec(F) do
begin
Mode:=fmClosed;
BufSize:=SizeOf(Buffer);
BufPtr:=@Buffer;
Name[0]:=#0;
OpenFunc:=@OpenCrtOut;
end;
end;
begin
AssignCrt(Output);
Rewrite(Output);
end.