Various versions of sendmail do various strange things with circular alias definitions. The qmail-local delivery mechanism lets each user manage several addresses, so there is no need for a special syntax to get around forwarding. Any message sent to alias will be forwarded to all of the addresses. A forwarding instruction may be split across several lines. This has the undesirable effect that a blank line behaves differently from a line containing a single space.
Internet addresses can legitimately start with a slash or vertical bar.
Note that file is read by fastforward , not newaliases , so the system administrator does not have to run newaliases every time file changes. When an alias includes the same recipient both inside and outside a mailing list, fastforward sends the message twice, once with each envelope sender.