The files that populate a queue directory are the
qf, df, and
xf files. The qf file (Section 11.11) contains envelope information and the
message's headers. The df file
(Section 11.2.2) contains the body of the message. The
xf file (Section 11.2.7), when
present, contains a copy of failed SMTP replies and other error
messages generated during a delivery attempt.
If the SuperSafe option (SuperSafe) is set to true, all messages are placed in
the queue prior to delivery. If that option is false (or interactive
beginning with V8.12) only messages that fail to be delivered on the
first attempt are placed into the queue. When a message is placed
into the queue, the qf and df
files are created. The permissions that the files get are determined
by this QueueFileMode option.
The QueueFileMode option is declared like this:
O QueueFileMode=perms configuration file (V8.12 and later)
-OQueueFileMode=perms command line (V8.12 and later)
define(`confQUEUE_FILE_MODE',`perms') mc configuration (V8.12 and later)
Here, perms is the permissions that will
be given to the created files. Those permissions are of type
octal. The default is 0600 (if the
real-user-id is the same as the
effective-user-id), and 0644 otherwise. If the
mode has the group-writable bit set (as in 0664), the
umask(2) is set to 0002 (disallow world-writable
permissions) just prior to the open(2) or
creat(2), and restored to its prior value just
Be careful to supply only an octal value to this option. If you
mistakenly give it a string (such as
QueueFileMode=o+rwx), you will find your queue
files being created with a mode of 000, and
sendmail will be unable to read them.
In general, it is recommended that queue files be created with the
narrowest permission possible. Unless you have a compelling reason to
change the defaults, you should leave them as is.
The QueueFileMode option is not safe. If specified
from the command line, it can cause sendmail to
relinquish its special privileges.