+The values stored in config.sh may be either single-quoted or
+double-quoted. Double-quoted strings are handy for those cases where you
+need to include escape sequences in the strings. To avoid runtime variable
+interpolation, any C<$> and C<@> characters are replaced by C<\$> and
+C<\@>, respectively. This isn't foolproof, of course, so don't embed C<\$>
+or C<\@> in double-quoted strings unless you're willing to deal with the
+consequences. (The slashes will end up escaped and the C<$> or C<@> will
+trigger variable interpolation)
+