strange test in psql:startup.c

        if (options.single_txn && options.action != ACT_FILE && options.action == ACT_NOTHING)
        {
                fprintf(stderr, _("%s: -1 can only be used in non-interactive mode\n"), pset.progname);
                exit(EXIT_FAILURE);
        }

the expression should be probably only?

options.single_txn && options.action == ACT_NOTHING)

Regards

Pavel