IBM Extension

OPEN Statement - Format 3 - TRANSACTION
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V |
>>-OPEN--I-O----file-name-3-+----------------------------------><
The OPEN statement can cause a program device to be implicitly acquired
for a TRANSACTION file. For a further discussion about the acquiring of program
devices, see the ACQUIRE Statement.
End of IBM Extension
- INPUT
- Permits opening the file for input operations.
Not allowed for FORMATFILE
or printer files.
- OUTPUT
- Permits opening the file for output operations. This phrase will cause
sequential and relative DISK files to be dynamically created if they do not
exist and CRTF option is specified. When a file is opened OUTPUT it contains
no records.
Existing records are removed (cleared) only for physical files.
For logical files, the file is treated as though EXTEND had been specified.
- I-O
- Permits opening the file for both input and output operations. The I-O
phrase can be specified only for files assigned to direct access devices,
such as DISK, DATABASE, and workstation files.
- EXTEND
- Permits opening the file for output operations.
The EXTEND phrase
must not be specified for a multiple file reel.
The EXTEND phrase is
not allowed for:
- FORMATFILE files
- Printer files
- DISKETTE files
- file-name-1, file-name-2, file-name-3, file-name-4
- Designates a file upon which the OPEN statement is to operate. If more
than one file is specified, the files need not have the same organization
or access. Each file-name must be defined in an FD entry in the Data Division,
and must not name a sort or merge file. The FD entry must be equivalent to
the information supplied when the file was defined.
- REVERSED
- Valid only for sequential single reel tape files.
- NO REWIND
- Valid only for sequential single reel tape files.