Why rlwrap echos “redundantly” what I type from the keyboard?

问题

I am using the rlwrap utility under linux for command line editing while using sql*plus. Everything is fine except that the utility echoes every command I enter from the keyboard. For example suppose that I typed this statement in the prompt:

SQL> select last_name from employees

the same statement would be echoed again in the terminal making the output looks like:

SQL> select last_name from employees
select last_name from employees

then when I complete the select statement on the next line, the output would look like:

SQL> select last_name from employees
select last_name from employees
  2  where department_id = 100;
where department_id = 100;

The problem is, with larger queries, this redundancy will clutter the terminal making the query hard to read, so any suggestions to suppress the unnecessary output would be really appreciated.

回答1:

This was a known bug with pre-0.36 rlwrap in vi mode. You don't mention your rlwrap version and editing mode (i.e. emacs or vi) but I would suggest upgrading to rlwrap-0.37 and filing a bug report with the rlwrap author if that doesn't help

来源：https://stackoverflow.com/questions/4485129/why-rlwrap-echos-redundantly-what-i-type-from-the-keyboard