Use the MAILFILEDSPREFIX statement to specify the prefix that is added to the SMTP mail data sets. If multiple MVS™ systems share the same volume for SMTP mail data sets, specify a unique prefix qualifier for each SMTP server on MAILFILEDSPREFIX.
Data sets created with this prefix contain mail that is in the process of being received or delivered. Each piece of mail queued for delivery occupies a minimum of 2 tracks.
MAILFILEDSPREFIX SMTP
All data sets are cataloged.