Nội dung của file dongho.tex

\usepackage{pdfbase}
\ExplSyntaxOn
\let\clockPdfAnnot\pbs_pdfannot:nnnn\let\clockPdfLastAnn\pbs_pdflastann:
\let\clockAppendToFields\pbs_appendtofields:n
\ExplSyntaxOff

\makeatletter
\def\clock@start#1#2#3{%
  function showtime#3(){%
    this.getField("digiclock.#3").value=util.printd("#1",new Date());%
    this.dirty=false;%
  }%
  showtime#3();%
  var digiclock#3=app.setInterval("showtime#3()",#2);%
}%
\newcounter{clock@num}%
\newlength\ex@height%
\newlength\clock@width%
\newlength\clock@height%
\def\digiclock{%
  \settowidth\clock@width{\clockformat}%
  \settoheight\clock@height{\clockformat}%
  \settoheight\ex@height{X}%
  \extractcolorspec{.}\clock@tempb% current color (\setcolor{...})
  \expandafter\convertcolorspec\clock@tempb{rgb}\clock@tempb%
  \edef\clock@tempa{\expandafter\clock@rgbcomp\clock@tempb\@nil}%
  \raisebox{\depth}{%
    \makebox[\clockfontscale\clock@width][l]{%
      \clockPdfAnnot{\clockfontscale\clock@width}%
                    {\clockfontscale\clock@height}{\clockfontscale\clock@height}{%
        /Subtype/Widget/FT/Tx/T (digiclock.\theclock@num) /Ff 1
        /DA (/\clockfont\space 0 Tf \clock@tempa\space rg)
        /MK<>
        /Q 2
        /BS <>
        /AA <<
          /PO <>
          /PC <>
        >>
      }%
    }%
    \vrule width 0pt height 0.5\ex@height depth 0.5\ex@height%
  }%
  \clockAppendToFields{\clockPdfLastAnn}%
  \stepcounter{clock@num}%
}
\def\clock@rgbcomp#1,#2,#3\@nil{#1 #2 #3}
\makeatother
\def\clockfont{Helvetica}
\def\clockfontscale{1.1}
\def\clockformat{HH:MM:ss}
\def\clockrefresh{1000}