Opening a loaded file (a file with records)

To open a file that already contains records, use OPEN INPUT, OPEN I-O, or OPEN EXTEND.

About this task

If you open a VSAM entry-sequenced or relative-record file as EXTEND, the added records are placed after the last existing records in the file.

If you open a VSAM key-sequenced file as EXTEND, each record you add must have a record key higher than the highest record in the file.

Related tasks  
Opening an empty file  
Working with VSAM data sets under z/OS and z/OS UNIX

Related references  
Statements to load records into a VSAM file  
z/OS DFSMS: Access Method Services for Catalogs