\chapter{Generic Operating System Services}

The modules described in this chapter provide interfaces to operating
system features that are available on (almost) all operating systems,
such as files and a clock.  The interfaces are generally modelled
after the \UNIX{} or C interfaces but they are available on most other
systems as well.  Here's an overview:

\begin{description}

\item[os]
--- Miscellaneous OS interfaces.

\item[time]
--- Time access and conversions.

\item[getopt]
--- Parser for command line options.

\item[tempfile]
--- Generate temporary file names.

\item[errno]
--- Standard errno system symbols.

\item[glob]
--- Unix shell style pathname pattern expansion.

\item[fnmatch]
--- Unix shell style pathname pattern matching.

\end{description}