How to get the current directory name in ConTeXt?

Question

Assume the file, source.tex is placed in /home/user/Birds/ and the user types context source.tex to compile the file. Is there a way for ConTeXt to retrieve the name of the folder that the file is located in (in this example, "Birds"), for use as a variable? This might be used, for example, to give the document a title, e.g. \title{\directoryname}.

• This will only be used on a Linux system and needn't be compatible with other systems.
• Directory names with spaces might appear, e.g. /home/user/Tropical\ Fish/.

Answer 1

\starttext
  \cldcontext {lfs.currentdir ()}
\stoptext

Answer 2

In ConTeXt:

\starttext

\ctxlua{context(os.resultof("pwd"))}

\stoptext

Answer 3

The \SetMacroToShellOutput defined below will set the given csname to the ouptut of the shell command that is provided to it. So

\SetMacroToShellOutput{\DirectoryNameWithPath}{pwd}

will set \DirectoryNameWithPath to the full Unix path of the current file name. You can use any Unix comamnds other than pwd and get the desired result. For instance

    \SetMacroToShellOutput{\FileNameWithoutPath}{basename `pwd`}

will set \FileNameWithoutPath to the current file name (without the path).

References:

• The macro \SetMacroToShellOutput is based on Specify file name shell access via \@@input.

Code:

\documentclass{article}

\makeatletter
\newcommand\SetMacroToShellOutput[2]{% 
  \begingroup\endlinechar=\m@ne\everyeof{\noexpand}%
  \edef\TempResult{\endgroup
    \expandafter\def\noexpand#1{%
      \@@input|"#2" }}%
  \TempResult}
\makeatother

\begin{document}
\SetMacroToShellOutput{\DirectoryNameWithPath}{pwd}%
DirectoryNameWithPath = \DirectoryNameWithPath
\end{document}