I would like to trash the mail received by a single qmail alias. I don't want any mail delivery errors, and I want qmail to be happy about having delivered the mail.
How can I do this, preferably without adding another local email account?
Create an alias with only a comment and no delivery instructions, like:
echo "# drop all messages on the floor" > ~alias/.qmail-devnull
Replace "devnull" with whatever alias name you need of course.