COBOL Manual for TNS and TNS/R Programs

Tape Input and Output

HP COBOL Manual for TNS and TNS/R Programs—522555-006

27-21

Labeled Tape Files

RECFORM Attribute (Conditional)

The RECFORM attribute is required unless you are bypassing labels (the value of the

LABELS attribute is BYPASS). The value of the RECFORM attribute must reflect the

type of records the tape has and must correspond to the RECORD CONTAINS clause

in the file description entry in the program.

BLOCKLEN Attribute (Conditional)

The BLOCKLEN attribute is required if the tape file has variable-length records (the

value of the RECFORM attribute is U) or if the tape file has fixed-length records (the

value of the RECFORM attribute is F), and the file description entry does not have a

BLOCK CONTAINS clause that specifies that the number of records per block is an

integer greater than one.

If the tape file has variable-length records, the value of the BLOCKLEN attribute

depends on the file’s maximum record size and open mode. If the open mode is

INPUT, the value of the BLOCKLEN attribute must be less than or equal to the

maximum record size; if the open mode is OUTPUT or EXTEND, the value of the

BLOCKLEN attribute must be greater than or equal to the maximum record size.

If the file has fixed-length records, the value of the BLOCKLEN attribute must be the

maximum record size, which is obtained from the BLOCK CONTAINS clause or from

the record description entry for the largest record.

RECLEN Attribute (Conditional)

The RECLEN attribute is required if the file has fixed-length records. Its value must be

the same as the value of the BLOCKLEN attribute (that is, the maximum record size).

If the record has variable-length records, the RECLEN attribute is unnecessary; if you

use it, its value is ignored.

Table 27-5. Correspondence Between RECORD CONTAINS Clause and

RECFORM Attribute Value

Record Length RECORD CONTAINS Clause RECFORM Attribute Value

Variable

(undefined)

RECORD CONTAINS min-length TO

max-length CHARACTERS

Fixed RECORD CONTAINS length-fixed

CHARACTERS