Doesn't look like it. I just tried running "yes | shuf -n 1" (using the latest version of GNU coreutils, 8.20) and its memory consumption increased steadily until I killed it.
It seems like this would be a really useful improvement, and I'm surprised that it doesn't already seem to have been requested on the coreutils issue tracker.
It seems like this would be a really useful improvement, and I'm surprised that it doesn't already seem to have been requested on the coreutils issue tracker.