Example return values:
\begin{itemize}
\item Unix: \texttt{\textit{prefix}/share/\textit{appname}}
- \item Windows: \texttt{C:$\backslash$Program Files$\backslash$\textit{appname}}
+ \item Windows: the directory where the executable file is located
\item Mac: \texttt{\textit{appname}.app/Contents/SharedSupport} bundle subdirectory
\end{itemize}