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#### CompareByte

Declaration:
  function CompareByte(var buf1,buf2;len:longint):longint;
Description:
  CompareByte compares two memory regions buf1,buf2 on a byte-per-byte basis for a total of len bytes.

  The function returns one of the following values:

  -1
    if buf1 and buf2 contain different bytes in the first len bytes, and the first such byte is smaller in buf1 than the byte at the same position in buf2.
  0
    if the first len bytes in buf1 and buf2 are equal.
  1
    if buf1 and buf2 contain different bytes in the first len bytes, and the first such byte is larger in buf1 than the byte at the same position in buf2.
Errors:
  None.
See also:
  CompareChar (468),CompareWord (472),CompareDWord (470)

Listing: refex/ex99.pp

Program Example99;
{ Program to demonstrate the CompareByte function. }
Const
ArraySize = 100;
HalfArraySize = ArraySize Div 2;
Var
Buf1,Buf2 : Array[1..ArraySize] of byte;
I : longint;
Procedure CheckPos(Len : Longint);
Begin
Write('First ',Len,' positions are ');
if CompareByte(Buf1,Buf2,Len)<>0 then
Write('NOT ');
Writeln('equal');
end;
begin
For I:=1 to ArraySize do
begin
Buf1[i]:=I;
If I<=HalfArraySize Then
Buf2[I]:=I
else
Buf2[i]:=HalfArraySize-I;
end;
CheckPos(HalfArraySize div 2);
CheckPos(HalfArraySize);
CheckPos(HalfArraySize+1);
CheckPos(HalfArraySize + HalfArraySize Div 2);
end.

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