Unit caretthread;

interface

uses
  classes,
  windows;

type
  Tcaretthread = Class(TThread)
    private
      frm: Cardinal;
    protected
       procedure execute; override;
    public
       constructor create; virtual;
       procedure sethandle(carethwnd: cardinal); virtual;
    end;

implementation

procedure Tcaretthread.execute;
var b: boolean;
begin
  b:=false;
  while b=false do hidecaret(frm);
end;

procedure Tcaretthread.sethandle(carethwnd: Cardinal);
begin
  frm := carethwnd;
end;

constructor Tcaretthread.create;
begin
  inherited create(true);
  freeOnTerminate := true;
end;

end.

  caret := Tcaretthread.create;
  caret.sethandle(richedit1.handle);
  caret.resume;