ref: 35cd44c563ec58e00a89109ef1f5450b08a3faa6
parent: 5c0def1850b2c09af300f09cd48f714f2505d217
author: Simon Tatham <anakin@pobox.com>
date: Sun Apr 23 10:53:11 EDT 2023
make_prefs_path(): tolerate NULL inputs. Just noticed that if prefs_dir() returns NULL, we'll already have passed it to this function before the calling functions get round to checking. I think it's less wordy all round to make this helper function propagate NULL than to mess about with lots of extra if statements in between all the calls.