more robust, notably wrt. interrupts;
#!/usr/bin/env bash
#
# Author: Makarius
#
# DESCRIPTION: raw ML process (interactive mode)
isabelle_admin_build jars || exit $?
eval "declare -a JAVA_ARGS=($ISABELLE_TOOL_JAVA_OPTIONS)"
mkdir -p "$ISABELLE_TMP_PREFIX" || exit $?
if type -p "$ISABELLE_LINE_EDITOR" > /dev/null
then
exec "$ISABELLE_LINE_EDITOR" isabelle java "${JAVA_ARGS[@]}" isabelle.ML_Console "$@"
else
echo >&2 "### No line editor: \"$ISABELLE_LINE_EDITOR\""
exec isabelle java "${JAVA_ARGS[@]}" isabelle.ML_Console "$@"
fi