%%
%% The LaTeX Companion, 3ed
%%
%% Example A-5-4 on page II-690 in "ifthen --- Advanced control structures".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{135.0pt}
%StartShownPreambleCommands
\usepackage{csquotes,ifthen,calc}
\newcounter{hours}\newcounter{minutes}
%StopShownPreambleCommands

\begin{document}
\newcommand{\printtime}{\setcounter{hours}{\time/60}%
      \setcounter{minutes}{\time-\value{hours}*60}%
      \ifthenelse{\value{hours}<10}{0}{}\thehours:%
      \ifthenelse{\value{minutes}<10}{0}{}\theminutes}
The current time is \enquote{\printtime}.
\end{document}