Using the ! (not) operation on a pipeline with zsh -fc
the wrong exit status in most versions of zsh later
than 2.4 and earlier than 4.0.3.
zsh -fc '\! print foo | grep bar' zsh -fc '\! \(exit 1\)'
The above commands should return success and failure
respectively, but instead they return failure and
success, as if the ! were not present.
The patch corrects this problem in 3.0.8.