Used exclusively for Delivery Status Notifications. R Contains a recipient address. There is one line for each recipient. S Contains the sender address. There is only one of these lines.
T Contains the message creation time used to compute when to time out the message.
V Specifies the version number of the queue file format used to allow new sendmail binaries to read queue files created by older versions. Defaults to version zero . Must be the first line of the file, if present. Used for Delivery Status Notifications only. To set the message time-out and queue processing interval, you must use a specific format for the time value.