The MinQueueAge option (MinQueueAge) sets the length of time a queued message must remain queued before delivery can again be tried. Each time sendmail processes a qf file, it subtracts the time stored in the K line from the current time and compares the result to the MinQueueAge. If sufficient time has not passed, the rest of the processing is skipped. (Note that this test is performed only if the qf file has been processed at least once; see the N line in N line).

The time stored in the K line looks like this:

K703531020

This number represents the date and time in seconds since January 1, 1970. Every time the qf file is processed (delivery is attempted), the K line is updated with the current time.