Executes Digital Test Manager commands contained in the specified
   file.

   Format

     @file-specification

1  –  Example

   DTM> @MAIL_TEST
   %DTM-S-LIBIS, Digital Test Manager library is DUA0:[USER01.DTMLIB]
   %DTM-S-RESUBMITTED, collection MAIL_TEST has been resubmitted
   -DTM-I-TEXT, Job MAIL_TEST (queue SYS$BATCH, entry 18) started on SYS$BATCH
   DTM>

   This example executes the command procedure MAIL_TEST.COM
   containing the commands SET LIBRARY DUA0:[USER01.DTMLIB] and
   SUBMIT MAIL_TEST.