+ fprintf(output, _(" ECHO control what input is written to standard output [all, queries]\n"));
The valid values in the help messages should be consistent with the values that the tab-completion displays. So in the case of ECHO, "errors" and "none" also should be added in the message. Thought?
In the help messages of some psql variables like ECHO_HIDDEN, valid values are not explained. Why not?
When this variable is set and a backslash command queries the database, the query is first shown. This way you can study the PostgreSQL internals and provide similar functionality in your own programs. (To select this behavior on program start-up, use the switch -E.) If you set the variable to the value noexec, the queries are just shown but are not actually sent to the server and executed.
There are no clear a set of valid values :( .. When I found a known fields in doc, I used it.
