Also don't attempt to delete the temporary file twice.

Audio from http://www.audiocheck.net/audiocheck_spectrotyper.php

This is a riddle for another day ...

This was a regression introduced by the cfg refactor

... and don't initialize global values twice while here

This is just to squelch Wconversion warnings on older GCC, making the
build output easier to read. No functional change.

Using strerror_r() w/ proper error checking is impossible, if the
system uses GNUisms (and losing _GNU_SOURCE's extensions is equally
painful)

Also, this change probably fixes a "abort() instead of error" bug.

This reverts commit 2ccc72c9.