Ordinarily, mailstats gathers the path to, and the name for, its statistics file from the sendmail configuration file. There will be times, however, when you will need to print statistics from information in another statistics file. Consider, for example, the desire to archive statistics files weekly for several years running. In such a scenario, you might run the following command to look at a statistics file from last year:

% mailstats -f /export/mail/archives/statsV3/1999/Dec/stat.25

But be aware that sendmail periodically updates the version of the statistics file. If you use the current version of mailstats to read an older version's statistics file, you will get an error something like this:

% mailstats -f /etc/sendmail.st
mailstats version (3) incompatible with /etc/sendmail.st version (2)

If you archive statistics files, you should also archive versions of mailstats with which to read them.