function marks
    if test (count $argv) -gt 0
        echo "Usage: marks"
    else
        set -l file_list (command ls $MARKPATH)
        if test (count $file_list) -eq 0
            echo "No marks currently defined."
        else
            set -l mark_list
            for file in $file_list
                if test -d $MARKPATH/$file -a -L $MARKPATH/$file
                    set mark_list $mark_list $file
                end
            end
            if test (count $mark_list) -eq 0
                echo "No marks currently defined."
            else
                set -l current_dir (pwd)
                for mark_name in $mark_list
                    cd $MARKPATH/$mark_name
                    set -l real_path (pwd)
                    echo "$mark_name -> $real_path"
                end
                cd $current_dir
            end
        end
    end
end