message: Fix Ctrl-C while entering multi-line quoted strings.
diff: @@ -58,6 +58,7 @@ pub(crate) fn terminate_quotes(shell: &mut Shell, command: String) -> Result<Str
  buffer.append(&command);
  }
  } else {
  + shell.flags ^= UNTERMINATED;
  return Err(());
  }
  }
  