Finally changed mktexlsr (in the TeX Live pretest) to support trees with spaces in the name. Long ago had lazily processed args with simply

trees="$trees $1" # which obviously loses when $1 contains a space

Since we certainly can't use arrays or any other advanced (ba)sh features, and rewriting in Perl would have been much more work, I now just write $1 to a temp file and then read it back with IFS=''. Of course names with newlines will still fail, but no one ever complains about those and doing \0 terminators was also too much trouble. I guess the goal is to be as lazy as possible (but no lazier)?