I didn't say the result had to be kept in memory. What happens to the list as it is read or after it is read is irrelevant. I'm saying you can't sort it without reading it all file names from the directory, so selectdir is completely useless to explorers.

I don't need to know all graphical explorers to know they don't use selectdir; I just need to know that a graphical explorer that doesn't sort file names is useless.