Describing the structure of a line-sequential file
In the FILE SECTION
, code a file description
(FD
) entry for the file. In the associated record
description entry or entries, define the record-name and
record length.
About this task
Code the logical size in bytes of the records by using
the RECORD
clause. Line-sequential files are stream
files. Because of their character-oriented nature, the physical records
are of variable length.
The following examples show how the FD
entry
might look for a line-sequential file:
With fixed-length records:
FILE SECTION.
FD COMMUTER-FILE
RECORD CONTAINS 80 CHARACTERS.
01 COMMUTER-RECORD.
05 COMMUTER-NUMBER PIC X(16).
05 COMMUTER-DESCRIPTION PIC X(64).
With variable-length records:
FILE SECTION.
FD COMMUTER-FILE
RECORD VARYING FROM 16 TO 80 CHARACTERS.
01 COMMUTER-RECORD.
05 COMMUTER-NUMBER PIC X(16).
05 COMMUTER-DESCRIPTION PIC X(64).
If you code the same fixed size and no OCCURS
DEPENDING ON
clause for any level-01 record description entries
associated with the file, that fixed size is the logical record length.
However, because blanks at the end of a record are not written to
the file, the physical records might be of varying lengths.
Allocating line-sequential files
Coding input-output statements for line-sequential files
Data division--file description entries
(Enterprise COBOL for z/OS Language Reference)