Today I was trying to upgrade all my brew kegs with
brew upgrade. But it trips up on libiconv.
You might try like I did and call brew with sudo but you get this message
Interesting, so now what? We could login as root but that might complicate things. What I did was give myself (a non-root user) access to the file. Like so
Now that directory belongs to the current user and brew has no issues modifying that directory!
sudo chown -R $USER /usr/local/include