This is the eighth in a series of “Nifty and Minimally Invasive qmail Tricks”, following

  1. qmail + SMTP AUTH + SSL + TLS - patches
  2. qmail + badrcptto - patches
  3. qmail + NetBSD nightly maintenance
  4. qmail + IMAP-before-SMTP
  5. qmail + spam filtering
  6. qmail + SMTP AUTH + TLS redux
  7. qmail + outbound DKIM

The mess822-QMAILQUEUE patch

This is not the QMAILQUEUE patch by Bruce Guenter that’s included in netqmail. When you want qmail-smtpd(8), for instance, to be able to modify or reject incoming messages by inserting a wrapper around qmail-queue(8), the QMAILQUEUE patch makes that easier.

The mess822-QMAILQUEUE patch is the exact same idea (and code), but for mess822.