MailFront

qmail Backend

  1. The qmail home directory is compiled into the program, and defaults to /var/qmail, but may be overridden by $QMAILHOME.
  2. Messages are delivered through the executable named in $QMAILQUEUE, or $QMAILHOME/bin/qmail-queue if it is not set.
  3. If qmail-queue exits non-zero, the qmail backend looks for an error message in $QQERRMSG_#, where # is the exit code of qmail-queue. As usual, exit codes between 11 and 40 indicate permanent errors, and all others indicate temporary errors.
  4. The qmail-queue PID is logged in success messages for correlation with the qmail logs.