Automatic Record Locking

If you are using automatic record locking, the READ statement acquires a record lock automatically. To avoid locking a record, use the WITH NO LOCK clause in the READ statement.

To specify automatic locking, use the LOCK MODE IS AUTOMATIC clause in the SELECT clause for the file:

 select fd-name
     assign to "muser.dat"
     lock mode is automatic
   ...
     read fd-name