doc-src/System/basics.tex

   \texttt{\$ISABELLE_HOME_USER/browser_info}.
   
 \item[\settdx{ISABELLE_LOGIC}] specifies the default logic to load if none is
   given explicitely by the user.  The default value is \texttt{HOL}.
   
+\item[\settdx{ISABELLE_LINE_EDITOR}] specifies the default line editor
+  for \texttt{isatool tty} (see also \S\ref{sec:tool-tty}).
+
 \item[\settdx{ISABELLE_USEDIR_OPTIONS}] is implicitly prefixed to the command
   line of any \texttt{isatool usedir} invocation (see also
   \S\ref{sec:tool-usedir}). This typically contains compilation options for
   object-logics --- \texttt{usedir} is the basic utility for managing logic
   sessions (cf.\ the \texttt{IsaMakefile}s in the distribution).