Function
A data description entry specifies the characteristics of a particular
item of data
or the characteristics of a programmer-defined type
of data which can then be used to specify the description of one or more
particular items of data.
A level 01 data description entry within the
Working-Storage Section or
File Section determines whether the data record and its subordinate data items
have local names or global names.
A level 01 data description in the Working-Storage
Section determines the internal or external attribute of the data record and
its subordinate data items.
General Formats
Format 1
Format 2
Format 3
Format 4
Syntax Rules
- The level-number in Format 1 can be any number from 01 through 49 or
77.
- The clauses can be written in any order with two exceptions: the
data-name-1 or FILLER clause
, if specified,
must immediately follow the level-number; the REDEFINES clause, when
used, must immediately follow the data-name-1 or FILLER clause
if either is specified; otherwise it must
immediately follow the level number.
- The P ICTURE clause must be
specified for every elementary item except an index data item,
a procedure pointer
a pointer or an internal floating-point data
item,
in which case use of this clause is prohibited.
- The words THRU and THROUGH are equivalent.
-
The EXTERNAL clause can be specified only in data
description entries in the Working-Storage Section whose level-number is 01.
-
The EXTERNAL
clause and the REDEFINES clause must not be specified in the same data
description entry.
-
The GLOBAL
clause can be specified only in data description entries whose level-number is
01.
-
Data-name-1 must be specified for any entry
containing the GLOBAL or EXTERNAL clause, or for record descriptions associated
with a file description entry which contains the EXTERNAL or GLOBAL clause.
-
The TYPEDEF clause can only be specified in data
description entries whose level-number is 01.
-
The TYPEDEF clause can only be used when
data-name-1 is also specified. In other words, it cannot be used in the same
data description with either an explicit or implicit FILLER clause.
Note that if the TYPEDEF clause is specified for
a group item, subordinate data descriptions can be defined with either an
implicit or explicit FILLER clause.
- The clauses SYNCHRONIZED,
PICTURE, JUSTIFIED, and
BLANK WHENZERO must not be
specified except for an elementary data item.
The SYNCHRONIZED clause can be specified for a
group item.
-
Literal-5 and integer-1 must not be floating-point
values and must not be negative values.
- If literal-5 is used as part of an expression, it must be a positive
or zero integer.
-
Data-name-2 and data-name-3 can be implicitly
qualified.
General Rules
- Format 3 is used for each condition-name. Each condition-name
requires a separate entry with level-n umber
88. Format 3 contains the name of the condition and the value, values, or range
of values associated with the condition-name. The condition-name entries for a
particular conditional variable must immediately follow the entry describing
the item with which the condition-name is associated. A condition-name can be
associated with any data description entry which contains a level-number except
the following:
- Another condition-name.
- A level 66 item.
- A group containing items with descriptions including JUSTIFIED,
SYNCHRONIZED or USAGE (other than USAGE IS DISPLAY).
- An index
or pointer
data item (see the section The USAGE IS INDEX Clause in
this chapter).
-
A constant-name.
-
Condition-names can be associated with internal
floating-point items.
Condition-names can be associated with external
floating-point items.
-
Format 4 defines a constant-name, which is a
symbolic name representing a constant value assigned to it when the source code
is passed through your COBOL system. Your COBOL system replaces each reference
to a constant-name by its value.
-
The TYPEDEF clause allows you to declare a group
or elementary data description as a type definition, which allows instances of
that data description to be declared as data items using data-name-1 as
typedef-name-1 in the USAGE clause. The type definition itself is not a data
item with allocated storage.
-
If the TYPEDEF clause is specified at a group
level, the components of the type definition are implicitly declared for any
data item of that type and are referenced using the usual COBOL rules of
qualification for the data item.
Function
The BLANK WHEN ZERO clause permits the blanking of an item when its
value is zero.
General Format
Syntax Rules
- The BLANK WHEN ZERO clause can be used only for an elementary item
whose PICTURE is specified as numeric (with implicit or explicit USAGE IS
DISPLAY) or numeric edited. (See the section The PICTURE Clause later in
this chapter.)
- The asterisk, when used as the zero suppression symbol, and the
clause BLANK WHEN ZERO should not appear in the same entry.
This construct is, however, permitted in which
case, zero suppression overrides the BLANK WHEN ZERO clause.
General Rules
- When the BLANK WHEN ZERO clause is used, the item will contain
nothing but spaces if the value of the item is zero.
- When the BLANK WHEN ZERO clause is used for an item whose PICTURE is
numeric, the category of the item is considered to be numeric edited.
Function
The BLOCK CONTAINS clause specifies the size of a physical record.
Although it is a part of the standard COBOL
definition, this feature is explicitly excluded from the X/Open COBOL language
definitions and should not be used in a conforming X/Open COBOL source program.
General Format
General Rules
-
This clause is documentary only.
Function
The CODE-SET clause specifies the character code set used to represent
data on the external media.
It can be specified only for files with record sequential
and line sequential
organization.
Although it is a part of the standard COBOL
definition, this feature is explicitly excluded from the X/Open COBOL language
definitions and should not be used in a conforming X/Open COBOL source program.
General Format
Directives
- In addition to Compiler directives which provide flagging and modify
the reserved word list, the following directive may impact either the syntax or
semantics described in this section.
- CHARSET - determines what is considered the native code-set.
Syntax Rules
- When the CODE-SET clause is specified for a file, all data in that
file must be described as usage is DISPLAY and any signed numeric data must be
described with the SIGN IS SEPARATE clause.
These restrictions do not apply.
- The alphabet-name clause referenced by the CODE-SET clause must not
specify the literal phrase.
These restrictions do not apply.
-
Identifier-1 can be qualified, but must not be
subscripted.
-
Each identifier-1 must be a data item described in
the same record description for the file, and must not itself be a record
description.
-
If the optional FOR phrase is specified, the
CODE-SET clause specifies the character code to be used for the data items
named. If the FOR phrase is not specified, the CODE-SET clause specifies the
character code to be used for the whole file.
- The native character set is used for any file, or data item in a
file, to which no CODE-SET clause applies.
General Rules
-
The data in the record area is always in ASCII. If
alphabet-name has been equated in the Special-Names paragraph to EBCDIC, then
data affected by the CODE-SET clause is translated from ASCII to EDCDIC as it
is written to the file; or from EBCDIC to ASCII as it is read from the file. If
alphabet-name has been equated in the Special-Names paragraph to STANDARD-1,
STANDARD-2, NATIVE, or ASCII, no translation is necessary.
-
For the purposes of this translation, any data
item to which a CODE-SET clause
applies is treated as alphanumeric. No account is taken of the class and
category of the item as described in its data description.
-
If identifier-1 has an OCCURS clause, the CODE-SET
clause applies to only the first occurrence of it. If identifier-1 has a
subordinate item with an OCCURS clause, the CODE-SET clause applies to the
whole of identifier-1.
Function
The DATA RECORDS clause serves only as documentation for the names of
data records with their associated file.
The DATA RECORDS clause of the file description
entry is classed as an obsolete element in the ANSI'85 standard and is
scheduled to be deleted from the next full revision of the ANSI Standard.
All dialects in this COBOL implementation fully
support this syntax. The FLAGSTD Compiler directive can be used to detect all
occurrences of this syntax.
Although part of the standard COBOL definition, this
feature is explicity excluded from the X/Open COBOL language definitions and
should not be used in a conforming X/Open COBOL source program.
General Format
Syntax Rules
- Data-name-1 and data-name-2 are the names of data records and should
have 01 level-number record descriptions, with the same names, associated with
them.
These data-names do not have to be associated
with any data description entry in the program.
General Rules
- The presence of more than one data-name indicates that the file
contains more than one type of data record. These records can be of differing
sizes, different formats, and so on. The order in which they are listed is not
significant.
Note: When using multiple 01 level items within an FD, if
the SELECT statement contains key definitions, the key sizes must be contained
within the minimum record length of that FD.
- Conceptually, all data
records within a file share the same area. This is in no way altered by the
presence of more than one type of data record within the file.
Function
A data-name specifies the name of the data being described. The word
FILLER can be used to specify an elementary item of the logical record that
cannot be referred to explicitly.
General Format
Syntax Rules
- The data-name or FILLER clause
, if specified,
must be the first word following the level-number in a data
description entry.
General Rules
- The key word FILLER can be used to name an elementary item or group
in a record. Under no circumstances can a FILLER item be referred to
explicitly. However, a data item defined with the key word FILLER can be used
as a conditional variable because such use does not require explicit reference
to the FILLER item but only to the value contained therein.
-
If this clause is omitted, the data item being
described is treated as though FILLER had been specified.
Function
The EXTERNAL clause specifies that a data item or a file connector is
external. The constituent data items and group items of an external data record
are available to every program in the run unit which describes that record.
General Format
Syntax Rules
- The EXTERNAL clause can be specified only in file description
entries, or in record description entries in the Working-Storage Section.
- In the same program, the data-name specified as the subject of the
entry whose level-number is 01 that includes the EXTERNAL clause must not be
the same data-name specified for any other data description entry which
includes the EXTERNAL clause.
- The VALUE clause must not be used in any data description entry that
includes, or is subordinate to an entry that includes, the EXTERNAL clause. The
VALUE clause can be specified for condition-name entries associated with such
data description entries.
-
Literal-1 must be a nonnumeric or a national
literal.
General Rules
- The data contained in the record named by the data-name clause is
external and can be accessed and processed by any program in the run unit which
describes and, optionally, redefines it subject to the following general rules.
- Within a run unit, if two or more programs describe the same external
data record, each record-name of the associated record description entries must
be the same and the records must define the same number of standard data format
characters. However, a program which describes an external record can contain a
data description entry including the REDEFINES clause which redefines the
complete external record, and this complete redefinition need not occur
identically in other programs in the run unit, unless the storage area required for the
redefinition is larger than the storage area required for the external data
record. See the section The REDEFINES Clause.
- Use of the EXTERNAL clause does not imply that the associated
file-name or data-name is a global name. See the section The GLOBAL
Clause later in this chapter.
- The file connector associated with this description entry is an
external file connecter.
-
See your COBOL system documentation on file
handling for further information on files with the EXTERNAL attribute.
-
Literal-1 identifies the external name of an
external data item or file connector. The same external name must be used by
all programs that reference the same external data item or file connector.
Function
The GLOBAL clause specifies that a data-name, a file-name, or a
report-name is a global name. A global name is available to every program
contained within the program which declares it.
General Format
Syntax Rules
- The GLOBAL clause can be specified only in data description entries
whose level-number is 01 in the File Section or the Working-Storage Section,
file description entries, or report description entries.
The GLOBAL clause can also be specified in the
Linkage Section.
- In the same Data Division, the data description entries for any two
data items for which the same data-name is specified must not include the
GLOBAL clause.
- If the SAME RECORD AREA clause is specified for several files, the
record description entries or the file description entries for these files must
not include the GLOBAL clause.
General Rules
- A data-name, file-name or report-name described using a GLOBAL clause
is a global name. All data-names subordinate to a global name are global names.
All condition-names associated with a global name are global names.
- A statement in a program contained directly or indirectly within a
program which describes a global name can reference that name without
describing it again. See the section Scope of Names in the chapter
Concepts of the COBOL Language.
- If the GLOBAL clause is used in a data description entry which
contains the REDEFINES clause, it is only the subject of that REDEFINES clause
which possesses the global attribute.
Function
The JUSTIFIED clause specifies non-standard positioning of data within a
receiving data item.
General Format
Syntax Rules
- The JUSTIFIED clause can be specified only at the elementary item
level.
- JUST is an abbreviation for JUSTIFIED.
- The JUSTIFIED clause cannot be specified for any data item described
as numeric or for which editing is specified.
- The JUSTIFIED clause cannot be specified for an index data item (see
the section The USAGE IS INDEX Clause)
, or for a pointer data item.
-
The JUSTIFIED clause cannot be specified for
external or internal floating-point data items.
General Rules
- When a receiving data item is described with the JUSTIFIED clause and
the sending data item is larger than the receiving data item, the leftmost
characters are truncated. When the receiving data item is described with the
JUSTIFIED clause and it is larger than the sending data item, the data is
aligned at the rightmost character position in the data item with space fill
for the leftmost character positions.
The contents of the sending data item are not taken into account,
that is, trailing spaces within the sending data item are not suppressed.
For example, if a data item PIC X(4) whose value is "A " (that
is, A followed by three spaces) is moved into a data item PIC X(6) JUSTIFIED
the result will be " A ". If the same data item is moved to one with PIC X(3)
JUSTIFIED the result will be " " that is, the leftmost character is
truncated.
- When the JUSTIFIED clause is omitted, the standard rules for aligning
data within an elementary item apply. (See the section Standard Alignment
Rules in the chapter Concepts of the COBOL Language.)
Function
The LABEL RECORDS clause specifies whether labels
are present.
The LABEL RECORDS clause is classed as an obsolete
element in the ANSI'85 standard and is scheduled to be deleted from the next
full revision of the ANSI Standard.
All dialects in this COBOL implementation fully
support this syntax. The FLAGSTD Compiler directive can be used to detect all
occurrences of this syntax.
Although it is a part of the standard COBOL
definition, this feature is explicitly excluded from the X/Open COBOL language
definitions and should not be used in a conforming X/Open COBOL source program.
General
Format
Syntax Rules
- This clause should be present in every file description entry.
It is not required.
-
Data-name-1 is the name of a label record and
should have a 01 level-number record description, with the same name,
associated with it.
-
Data-name-1 must not appear in the DATA RECORDS
clause for the file.
-
Both LABEL RECORDS IS and LABEL RECORD ARE are
accepted as valid syntax.
General Rule
-
This clause is documentary only.
Function
The level-number shows the hierarchy of data within a logical record. In
addition, it is used to identify entries for working-storage items, linkage
items, condition-names
, constant-names
and the RENAMES clause.
General Format
Syntax Rules
- A level-number is required as the first element in each data
description entry.
- Data description entries subordinate to an FD, CD, or SD entry must
have level-numbers with the values 01
through 49, 66
,78
or 88. (See the section The FILE Description earlier in this
chapter.)
- Data description entries in the Report Section and Screen Section
must have level-numbers with the values 01 through 49
, or 78
- Data description entries in the Working-Storage Section
, Local-Storage
and Linkage Section must have level-numbers
with the values 01 through 49, 66, 7 7
, 78
or 88.
- A level-number can be a one or two digit number.
General Rules
- The level-number 01 identifies the first entry in each record
description.
- Special level numbers have been assigned to certain entries where
there is no real concept of level hierarchy:
- The level-number 77 is assigned to identify noncontiguous
working-storage data items and noncontiguous linkage data items. It can be used
only as described by Format 1 of the data description skeleton earlier in this
chapter.
- Level number 66 is assigned to identify RENAMES entries and can
be used only as described in Format 2 of the data description skeleton earlier
in this chapter.
- Level number 88 is assigned to entries which define
condition-names associated with a conditional
variable and can be used only as described in Format 3 of the data description
skeleton earlier in this chapter.
-
Level number 78 is assigned to entries which
define constant-names. It can be used only as described in Format 4 of the data
description skeleton earlier in this chapter.
- Multiple level 01 entries subordinate to a CD, FD or SD entry
represent implicit redefinitions of the same area.
The reserved word LINAGE-COUNTER is a name for a special register
generated by the presence of a LINAGE clause in a file description entry for a
record sequential file. The implicit description is that of an unsigned integer
whose size is equal to the size of integer-1 or the data item referenced by
data-name-1 in the LINAGE clause.
Function
The LINAGE clause allows the user to specify the depth of a logical page
in terms of number of lines. The user can also specify the size of the top and
bottom margins on the logical page, and the line number, within the page body,
at which the footing area begins.
It can be specified only for files with sequential organization.
General Format
Syntax Rules
- Data-name-1, data-name-2, data-name-3 and data-name-4 must reference
elementary unsigned integer data items.
- The value of integer-1 must be greater than zero.
- The value of integer-2 must not be greater than integer-1.
- The value of integer-3 and integer-4 can be zero.
General Rules
- The LINAGE clause allows the user to specify the size of a logical
page in terms of number of lines. The logical page size is the sum of the
values referenced by each phrase except the FOOTING phrase. If the
FOOTING phrase is not specified, the
values for these functions are zero and no end-of-page condition independent of
the page overflow condition
exists.
There is not necessarily any relationship between the size of the
logical page and the size of a physical page.
- The value of integer-1 or the data item referenced by data-name-1
specifies the number of lines that can be written and/or spaced on the logical
page. The value must be greater than zero. That part of the logical page in
which these lines can be written
and/or spaced is called the page body.
- The value of integer-2 or the data item referenced by data-name-2
specifies the line number within the page body at which the footing area
begins. The value must be greater than zero and not greater than the value of
integer-1 or the data item referenced by data-name-1.
The footing area comprises the area of the logical page between the
line represented by the value of integer-2 of the data item referenced by
data-name-2, and the line represented by the value of integer-1 or the data
item referenced by data-name-1, inclusive.
- The value of integer-3 or the data item referenced by data-name-3
specifies the number of lines that comprise the top margin on the logical page.
The value can be zero.
The value of integer-4 or the data item referenced by data-name-4
specifies the number of lines that comprise the bottom margin on the logical
page. The value can be zero.
- The value of integer-1, integer-3, and integer-4, if specified, will
be used at the time the file is opened by the execution of an OPEN statement
with the OUTPUT phrase, to specify the number of lines that comprise each of
the indicated sections of a logical page. The value of integer-2, if specified,
will be used at that time to define the footing area. These values are used for
all logical pages written for the file during a given execution of the program.
- The values of the data items referenced by data-name-1, data-name-3,
and data-name-4, if specified at the time an open statement with the OUTPUT
phrase is executed for the file, will be used to specify the number of lines
that are to comprise each of the indicated sections for the first logical page.
The value of the data item referenced by data-name-2, if specified,
will be used at the time an OPEN statement with the OUTPUT phrase is executed
for the file to define the footing area for the first logical page.
- A LINAGE-COUNTER is generated by the presence of a LINAGE clause. The
value in the LINAGE-COUNTER at any
one time represents the line number at which the device is positioned within
the current page body. The rules governing the LINAGE-COUNTER are as follows:
- A separate LINAGE-COUNTER is supplied for each file described in
the File Section whose file description entry contains a LINAGE clause.
- LINAGE-COUNTER can be referenced, but can not be modified, by
PROCEDURE DIVISION statements. Since more than one LINAGE-COUNTER can exist in
a program, the user must qualify LINAGE-COUNTER by file-name when necessary.
- Each logical page is contiguous to the next with no additional
spacing provided.
- The values of the data items, at the time a WRITE statement with the
ADVANCING PAGE phrase is executed or page overflow condition occurs (see the
section The WRITE Statement later in this chapter), will be used to
specify the number of lines that are to comprise each of the indicated sections
for the next logical page.
- The value of the data item referenced by data-name-2, if specified,
will be used at the time a WRITE statement with the ADVANCING PAGE phrase is
executed or a page overflow condition occurs, to define the footing area for
the next logical page.
- LINAGE-COUNTER is automatically modified, according to the following
rules, during the execution of a WRITE statement to an associated file:
- When the ADVANCING PAGE phrase of the WRITE statement is
specified, the LINAGE-COUNTER is automatically reset to one.
- When the ADVANCING identifier-2 or integer phrase of the WRITE
statement is specified, the LINAGE-COUNTER is incremented by integer or the
value of the data item referenced by identifier-2.
- When the ADVANCING phrase of the WRITE statement is not
specified, the LINAGE-COUNTER is incremented by the value one. (See the section
The WRITE Statement later in this chapter.)
- The value of LINAGE-COUNTER
is automatically reset to one when the device is repositioned to the first line
that can be written on for each of the succeeding logical pages. (See the
section The WRITE Statement later in this chapter.)
- The value of LINAGE-COUNTER is automatically set to one when an OPEN
statement is executed for the associated file.
Function
The OCCURS clause eliminates the need for separate entries for repeated
data items and supplies information required for the application of subscripts
or indices.
General Formats
Format 1
Format 2
Directives
- In addition to Compiler directives which provide flagging and modify
the reserved word list, the following directives may impact either the syntax
or semantics described in this section.
- ODOOSVS - requests OS/VS COBOL compatible processing of the
OCCURS DEPENDING ON clause.
- ODOSLIDE - controls the processing of nested OCCURS DEPENDING ON
clauses and fixed data following an OCCURS DEPENDING ON clause.
Syntax Rules
- Where both integer-1 and integer-2 are used, integer-1 must be
greater than
or equal to
zero and integer-2 must be greater than
or equal to
integer-1.
In Format 2, if "integer-1 TO" is
omitted, the default value one is assumed.
- The data description of data-name-1 must describe an integer.
- Data-name-1, data-name-2, data-name-3, ... can be qualified.
- Data-name-2 must be either the name of the entry containing the
OCCURS clause or the name of an entry subordinate to the entry containing the
OCCURS clause.
This restriction is removed.
- Data-name-3, and so on, must be the name of an entry subordinate to
the group item which is the subject of this entry.
This restriction is removed.
- An INDEXED BY phrase is
required if the subject of this entry, or an entry subordinate to this entry,
is to be referred to by indexing,
unless it is to be indexed by an index defined
for another table (see the section Indexing in the chapter Concepts
of the COBOL Language).
The index-name identified by this clause is not defined elsewhere,
and not being data, cannot be associated with any data hierarchy.
- A data description entry that contains Format 2 of the OCCURS clause should only be followed,
within that record description, by data description entries which are
subordinate to it.
A data description entry that contains Format 2
of the OCCURS clause can be followed, within that record description, by data
description entries which are not subordinate to it. The positions of these
entries within the record will vary at run time with the value of the data item
referenced in the DEPENDING
ON clause
unless the NOODOSLIDE Compiler directive is set.
In this case, the containing record is considered as always containing the
maximum number of occurrences of the Format 2 item, irrespective of the value
of data-name-1. If the ODOSLIDE
Compiler dir ective is set,
when the value of data-name-1 is changed, the
position referenced by identifiers following, but not subordinate to, the table
is changed. The data these items contain can be lost.
- The OCCURS clause cannot be specified in a data description entry
that:
- has a 66 or
88 level-number
- describes an item whose size is variable. The size of an item is
variable if the data description of any subordinate item contains Format 2 of
the OCCURS clause.
An OCCURS clause can be specified for a
data description subordinate to another item with a Format 2 OCCURS clause.
- The OCCURS clause should not be specified in a data description entry
at the 01 level or as a
77 level-number.
This restriction is removed.
- In Format 2, the data item defined by data-name-1 must not occupy a
character position within the range of the first character position defined by
the data description entry containing the OCCURS clause and the last character
position defined by the record description entry containing that OCCURS clause.
If the ODOSLIDE Compiler directive is set,
data-name-1 must have a fixed location.
- If data-name-2 is not the subject of this entry, then:
- all of the items identified by the data-names in the KEY IS
phrase must be within the group item which is the subject of this entry
- items identified by the data-name in the KEY IS phrase must not
contain an OCCURS clause
- there must not be any entry that contains an OCCURS clause
between the items identified by the data-names in the KEY
IS phrase and the subject of this entry.
- Index-name-1, index-name-2, ... must be unique words within the
program.
Index-name-1, index-name-2, ... need not be
unique and can be qualified by the data-name which is the subject of this
entry.
-
The OCCURS
clause can be specified for external or internal floating-point data items.
General Rules
- The OCCURS clause is used in defining
tables and other homogenous sets of repeated data items. Whenever the OCCURS
clause is used, the data-name which is the subject of this entry must be either
subscripted or indexed whenever it is referred to in a statement other than
SEARCH
, SORT
or USE FOR DEBUGGING. Further, if the subject of this entry is the
name of a group item, then all data-names belonging to the group must be
subscripted or indexed whenever they are used as operands, except as the object
of a REDEFINES clause. (See the sections Subscripting,
Indexing and
Identifier in the chapter Concepts of the COBOL Language.)
- Except for the OCCURS clause itself, all data description clauses
associated with an item whose description includes an OCCURS clause apply to
each occurrence of the item described. (See the restriction in general rule 20
under Data Description Entries Other Than Condition-Names
and Constant-Names.)
- Data-name-1 must have a fixed location, and must not follow an item
that contains an OCCU RS
DEPENDING ON clause.
- The nu mber of occu
rrences of the subject entry is defined as follows:
- In Format 1, the value of integer-2 represents the exact number
of occurrences.
- In Format 2, the current value of the data item referenced by
data-name-1 represents the number of occurrences.
This format specifies that the subject of this entry has a
variable number of occurrences. The value of integer-2 represents the maximum
number of occurrences and the value of integer-1 represents the minimum number
of occurrences. This does not imply that the length of the subject of the entry
is variable, but that the number of occurrences is variable.
The value of the data item referenced by data-name-1 must fall
within the range of integer-1 through integer-2. Reducing the value of this
data item makes the contents of data items, whose occurrence numbers now exceed
the value of the data item referenced by data-name-1, unpredictable.
-
When a group item, having subordinate to it an
entry that specifies Format 2 of the OCCURS
clause, is referenced, the part of the table area
used in the operation is determined as follows:
- If the data item referenced by data-name-1 is outside the group,
only that part of the table area that is specified by the value of the data
item referenced by data-name-1 at the start of the operation will be used.
- If the data item referenced by data-name-1 is included in the
same group and the group data item is referenced as a sending item, only that
part of the table area that is specified by the value of the data item
referenced by data-name-1 at the start of the operation will be used in the
operation. If the group is a receiving item, the maximum length of the group
will be used.
- The KEY IS phrase is used to indicate that the repeated data is
arranged in ascending or descending
order according to the values contained in data-name-2, data-name-3, and so on.
The ascending or descending order is determined according to the rules for
comparison of operands (see the sections Comparison of Numeric Operands
and Comparison of Nonnumeric Operands). The data-names are listed in
their descending order of significance.
Function
The PICTURE clause describes the general characteristics and editing
requirements of an elementary item.
General Format
Syntax Rules
- A PICTURE clause can be
specified only at the elementary item level.
- A character-string consists of certain allowable combinations of
characters in the COBOL character set used as symbols. The allowable
combinations determine the category of the elementary item.
- The maximum number of characters allowed in the character- string is
30.
- The PICTURE clause must be
specified for every elementary item except an index data item
, pointer,
or internal floating-point data item
or the subject of a RENAMES clause, in which case use of this clause
is prohibited.
- PIC is an abbreviation for PICTURE.
- The asterisk when used as the zero suppression symbol and the clause
BLANK WHEN ZERO should not appear in the same entry.
This construct is, however, permitted, in which
case zero suppression overrides the BLANK WHEN ZERO clause.
- An integer in parentheses following a character indicates that the
character is repeated the number of times shown by the integer.
General Rules
There are six categories of data that can be described with a PICTURE
clause: alphabetic, numeric, alphanumeric, alphanumeric edited, numeric edited,
and external floating-point
. General rules within these categories are given below:
Alphabetic Data Rules
- Its PICTURE character-string can only contain the symbols
"A" and "B".
Its PICTURE character-string can contain only
the symbol "A".
- Its contents when represented in standard data format must be one or
more alphabetic characters.
Numeric Data Rules
- Its PICTURE character-string can contain only the symbols
"9", "P", "S", and "V". The number of
digit positions that can be described by the PICTURE character-string must
range from 1 to 18 inclusive.
- If unsigned, the data in standard data format must be a combination
of the Arabic numerals "0", "1", "2", "
3", "4", "5", "6", "7",
"8", and "9"; if signed, the item can also contain a
"+", "–", or other representation of an operational
sign. (See the section The SIGN Clause later in this chapter.)
Numeric Data can also be held in formats other than standard data format
(see the section The USAGE Clause later in this chapter and the section
Selection Of Character Representation And Radix in the chapter
Concepts of the COBOL Language).
Alphanumeric Data Rules
- Its PICTURE character-string is restricted to certain combinations of
the symbols " A", "X", "9", and the item is
treated as if the character-string contained all X"s. A PICTURE
character-string which contains all A"s or all 9"s does not define an
alphanumeric item.
- Its contents when represented in standard data format can consist of
any characters in the computer's character set.
Alphanumeric Edited Data Rules
- Its PICTURE character-string is restricted to certain combinations of
the following symbols: "A", "X", " 9",
"B", "0", and "/" as follows:
- The character-string must contain at least one "B" and
at least one "X" or at least one "0" (zero) and at least
one "X" or at least one "/" (slash) and at least one
"X", or:
- The character-string must contain at least one "0"
(zero) and at least one "A" or at least one "/" (slash) and
at least one "A".
- Its contents when represented in standard data format can consist of
any characters in the computer's character set.
Numeric Edited Data Rules
- Its PICTURE character-string is restricted to certain combinations of
the symbols "B", "/", "P", "V" ,
"Z", "0", "9", ",", ".",
"*", "+", "–", "CR",
"DB", and the currency symbol. The
allowable combinations are determined from the order of precedence of symbols
and the editing rules as follows:
- The number of digit positions that can be represented in the
PICTURE character-string must range from 1 to 18 inclusive.
- The character-string must contain at least one "0" ,
"B", "/", "Z", "*", "+",
",", ".", "–", "CR" ,
"DB", or currency symbol.
- The contents of the character positions that represent a digit must
be one of the numerals.
- If all character positions in the PICTURE character-string are
represented by an insertion character, at least one of the insertion characters
must be positioned to the left of the decimal point.
External Floating-point Data Items
- The PICTURE string must have the following form:
A sign character must immediately precede both the mantissa and the
exponent.
A "+" sign indicates that a positive sign will be used in
the output to represent positive values and that a negative sign will represent
negative values.
A "–"sign indicates that a blank will be used in the
output to represent positive values and that a negative sign will represent
negative values.
Each sign position occupies one byte of storage.
mantissa
The mantissa can contain the symbols:
9 . V
An actual decimal point can be represented with a period while an
assumed decimal point is represented by a V. Either an actual or an assumed
decimal point must be present in the mantissa; the decimal point can be
leading, embedded or trailing. The mantissa can contain from 1 to 16 numeric
characters.
E
Indicates the exponent.
exponent
The exponent must be a PIC "99".
- The OCCURS, REDEFINES and RENAMES clauses can be associated with
external floating-point items.
- The SIGN clause is documentary only and has no effect on the
representation of the sign.
- The SYNCHRONIZED clause is documentary only.
- The following clauses are invalid with external floating-point items:
BLANK WHEN ZERO
JUSTIFIED
VALUE
Elementary Item Size
The size of an elementary
item, where size means the number of character positions occupied by the
elementary item in standard data format, is determined by the number of
allowable symbols that
represent character positions. An integer which is enclosed in parentheses
following the symbols "A", ",", "X" ,
"9", "P", "Z", "*", "B",
"/", "0", "+", "–", or the
currency symbol indicates the number of replications of the symbol. Note that
the following symbols can appear only once in a given PICTURE: "S" ,
"V", ".",
"E",
"C R", and "D
B".
Symbols Used
The functions of the symbols used to describe an elementary item are
explained as follows:
| A |
Each "A" in the character-string represents
a character position which can contain only a letter of the alphabet or a
space. |
| B |
Each "B" in the character-string represents
a character position into which the space character will be inserted. |
|
E |
Marks the start of the exponent in an external
floating-point item. The exponent occupies 1 byte of storage at run time. |
| P |
Each "P" indicates an assumed decimal
scaling position and is used to specify the location of an assumed decimal
point when the point is not within the number that appears in the data item.
The scaling position character "P" is not counted in the size of the
data item. Scaling position characters are counted in determining the maximum
number of digit positions (18) in numeric edited items or numeric items. The
scaling position character "P" can appear only to the left or right
as a continuous string of "P"s within a PICTURE description; since
the scaling position character "P" implies an assumed decimal point
(to the left of "P" s if "P"s are leftmost PICTURE
characters and to the right if "P"s are rightmost PICTURE
characters), the assumed decimal point symbol "V" is redundant as
either the leftmost or rightmost character within such a PICTURE description.
The character "P" and the insertion character
"." (period) cannot both occur in the same PICTURE character-string.
If, in any operation involving conversion of data from one form of internal
representation to another, the data item being converted is described with the
PICTURE character "P", each digit position described by a
"P" is considered to contain the value zero, and the size of the data
item is considered to include the digit positions so described.
In certain operations that reference a data
item whose PICTURE character-string contains the symbol "P", the
algebraic value of the data item is used rather than the actual character
representation of the data item. This algebraic value assumes the decimal point
in the prescribed location and zero in place of the digit position specified by
the symbol "P". The size of the value is the number of digit
positions represented by the PICTURE character-string. These operations are any
of the following:
- Any operation requiring a numeric sending operand.
- An elementary MOVE statement where the sending operand is
numeric and its PICTURE character-string contains the symbol "P".
- A MOVE statement where the sending operand is numeric edited
and its PICTURE character-string contains the symbol "P" and the
receiving operand is numeric or numeric edited.
- A comparison operation where both operands are numeric.
In all other operations the digit positions
specified with the symbol "P" are ignored and are not counted in the
size of the operand. |
| S |
The letter "S" is used in a character-string
to indicate the presence, but neither the representation nor, necessarily, the
position of an operational sign; it must be written as the leftmost character
in the PICTURE. The "S" is not counted in determining the size (in
terms of standard data format characters) of the elementary item unless the
entry is subject to a SIGN clause which specifies the optional SEPARATE
CHARACTER phrase. (See the section The SIGN Clause in this chapter.)
|
| V |
The letter "V" is used in a character-string
to indicate the location of the assumed decimal point and can only appear once
in a character-string. The "V" does not represent a character
position and therefore is not counted in the size of the elementary item. When
the assumed decimal point is to the right of the rightmost symbol in the string
the "V" is redundant. |
| X |
Each "X" in the character-string is used to
represent a character position which contains any allowable character from the
computer's character set. |
| Z |
Each "Z" in a character-string can only be
used to represent the leftmost numeric character positions which will be
replaced by a space character when the contents of that character position is
zero. Each "Z" is counted in the size of the item. |
| 9 |
Each "9" in the character-string represents
a character position which contains a numeral and is counted in the size of the
item. |
| 0 |
Each "0" (zero) in the character-string
represents a character position into which the numeral zero will be inserted.
The "0" is counted in the size of the item. |
| / |
Each "/" (slash) in the character-string
represents a character position into which the slash character will be
inserted. The "/" is counted in the size of the item. |
| , |
Each "," (comma) in the character-string
represents a character position into which the character "," will be
inserted. This character position is counted in the size of the item. The
insertion character "," must not be the last character in the PICTURE
character-string.
The insertion character "," can be
the last character in the PICTURE character-string. |
| . |
When the character "." (period) appears in
the character-string it is an editing symbol which represents the decimal point
for alignment purposes and, in addition, represents a character position into
which the character "." will be inserted. The character "."
is counted in the size of the item. For a given program the functions of the
period and comma are exchanged if the clause DECIMAL-POINT IS COMMA is stated
in the SPECIAL-NAMES paragraph. In this exchange the rules for the period apply
to the comma and the rules for the comma apply to the period wherever they
appear in a PICTURE clause. The insertion character " ." must not be
the last character in the PICTURE character-string.
The insertion character "." can be
the last character in the PICTURE character-string. |
| +, –, CR,
DB |
These symbols are used as editing sign control
symbols. When used, they represent the character position into which the
editing sign control symbol will be placed. The symbols are mutually exclusive
in any one character-string and each character used in the symbol is counted in
determining the size of the data item. |
| * |
Each "*" (asterisk) in the character-string
represents a leading numeric character position into which an asterisk will be
placed when the contents of that position is zero. Each "*" is
counted in the size of the item. |
| cs |
The currency symbol in the character-string represents
a character position into which a currency symbol is to be placed. The currency
symbol in a character-string is represented by either the currency sign or by
the single character specified in the CURRENCY SIGN clause in the SPECIAL-NAMES
paragraph. The currency symbol is counted in the size of the item. The
CURRENCY Compiler directive also
affects the currency symbol used. |
Editing Rules
Two general methods of performing editing in the PICTURE clause are
available: insertion or
suppression and replacement.
Four types of insertion editing are available:
- Simple insertion
- Special insertion
- Fixed insertion
- Floating insertion
Two types of suppression and replacement editing are available:
- Zero suppression and replacement with spaces
- Zero suppression and replacement with asterisks
The type of editing which can be performed upon an item is dependent
upon the category to which the item belongs. Table 8-1 specifies which type of
editing can be performed upon a given category.
Table 8-1: Editing Types For Data Categories
| Category |
Type of Editing |
| Alphabetic |
Simple insertion "B" only 1 |
| Numeric |
None |
| Alphanumeric |
None |
| Alphanumeric Edited |
Simple insertion "0", "B" and
"/" |
| Numeric Edited |
All 2 |
| DBCS |
Simple insertion |
| External floating-point |
Special insertion |
Notes:
-
In the ANSI'74 standard, PICTURE clauses
containing both "A" and "B" are treated as simple insertion
in category Alphabetic. As the ANSI'85 standard does not support "B"
in the Alphabetic category, the ANSI'85 standard considers this PICTURE as
simple insertion in the Alphanumeric Edited category.
- Floating insertion editing and editing by zero suppression and
replacement are mutually exclusive in a PICTURE clause. Only one type of
replacement can be used with zero suppression in a PICTURE clause.
Simple
Insertion Editing
The "," (comma), "B" (space), "0" (zero),
and " /" (slash) are used as the insertion characters. The insertion
characters are counted in the size of the item and represent the position in
the item into which the character will be inserted.
Special Insertion Editing
This type of editing is valid for either numeric
edited items or external floating-point items.
The "." (period) is used as the insertion character. In
addition to being an insertion character it represents the decimal point for
alignment purposes. The insertion character used for the actual decimal point
is counted in the size of the item. The use of the assumed decimal point,
represented by the symbol "V" and the actual decimal point,
represented by the insertion character, in the same PICTURE character-string is
disallowed. The result of special insertion editing is the appearance of the
insertion character in the item in the same position as shown in the
character-string.
Fixed
Insertion Editing
The currency symbol and the editing sign control symbols "+" ,
"–", "CR", "DB" are the insertion
characters. Only one currency symbol and only one of the editing sign control
symbols can be used in a given PICTURE character-string. When the symbols
"CR" or "DB" are used, they represent two character
positions in determining the size of the item and they must represent the
rightmost character positions that are counted in the size of the item. The
symbol "+" or "–", when used, must be either the
leftmost or rightmost character position to be counted in the size of the item.
The currency symbol must be the leftmost character.
Table 8-2 : Editing Symbols in PICTURE Character-Strings
| Editing Symbol in Picture
Character-string |
Result |
| Data Item Positive or Zero |
Data Item Negative |
| + |
+ |
– |
| – |
space |
– |
| CR |
2 spaces |
CR |
| DB |
2 spaces |
DB |
Floating Insertion Editing
The currency symbol and the editing sign control symbols "+"
and "–" are the floating insertion characters and as such are
mutually exclusive in a given PICTURE character-string.
Floating insertion editing is indicated in a PICTURE character-string by
using a string of at least two of the floating insertion characters. This
string of floating insertion characters can contain any of the simple insertion
characters or have simple insertion characters immediately to the right of this
string. These simple insertion characters are part of the floating string.
When the floating insertion character is the currency symbol, this
string of floating insertion characters can have one of the editing sign
control symbols "+", "–", "CR" or "
DB" immediately to the right of this string.
The leftmost character of the floating insertion string represents the
leftmost limit of the floating symbol in the data item. The rightmost character
of the floating string represents the rightmost limit of the floating symbols
in the data item.
The second floating character from the left represents the leftmost
limit of the numeric data that can be stored in the data item. Non-zero numeric
data can replace all the characters at or to the right of this limit.
Floating insertion editing can be represented in a PICTURE
character-string in only two ways. One way is to represent any or all of the
leading numeric character positions on the left of the decimal point by the
insertion character. The other way is to represent all of the numeric character
positions in the PICTURE character-string by the insertion character.
If the insertion characters are only to the left of the decimal point in
the PICTURE character-string, the result is that a single floating insertion
character will be placed into the character position immediately preceding
either the decimal point or the first non-zero digit in the data represented by
the insertion symbol string, whichever is farther to the left in the PICTURE
character-string. The character positions preceding the insertion character are
replaced with spaces.
If all numeric character positions in the PICTURE character-string are
represented by the insertion character, the result depends upon the value of
the data. If the value is zero, the entire data item will contain spaces. If
the value is not zero, the result is the same as when the insertion character
is only to the left of the decimal point.
If all numeric positions in the PICTURE character
string are represented by the insertion character, at least one numeric
position must be to the left of the assumed or actual decimal point.
To avoid truncation, the minimum size of the PICTURE character-string
for the receiving data item must be the number of characters in the sending
data item, plus the number of non-floating insertion characters being edited
into the receiving data item, plus one for the floating insertion character.
Zero
Suppression Editing
The suppression of leading zeros in numeric character positions is
indicated by the use of the alphabetic character "Z" or the character
"*" (asterisk) as suppression symbols in a PICTURE character- string.
These symbols are mutually exclusive in a given PICTURE character-string. Each
suppression symbol is counted in determining the size of the item. If
"Z" is used, the replacement character will be the space and if the
asterisk is used, the replacement character will be "*".
Zero suppression and replacement is indicated in a PICTURE
character-string by using a string of one or more of the allowable symbols to
represent leading numeric character positions which are to be replaced when the
associated character position in the data contains a zero. Any of the simple
insertion characters embedded in the string of symbols or to the immediate
right of this string are part of the string.
Zero suppression can be represented in a PICTURE character-string in
only two ways. One way is to represent any or all of the leading numeric
character positions to the left of the decimal point by suppression symbols.
The other way is to represent all of the numeric character positions in the
PICTURE character-string by suppression symbols.
If the suppression symbols appear only to the left of the decimal point,
any leading zero in the data which corresponds to a symbol in the string is
replaced by the replacement character. Suppression terminates at the first
non-zero digit in the data represented by the suppression symbol string or at
the decimal point, whichever is encountered first.
If all numeric character positions in the PICTURE character-string are
represented by suppression symbols and the value of the data is not zero, the
result is the same as if the suppression characters were only to the left of
the decimal point. If the value is zero and the suppression symbol is
"Z", the entire data item will be spaces. If the value is zero and
the suppression symbol is "*", the data item will be all
"*" except for the actual decimal point.
The symbols "+", "–", "*", "
Z" and the currency symbol, when used as floating replacement characters,
are mutually exclusive within a given character-string.
Precedence Rules
Table 8-3 shows the order of precedence when using characters as symbols
in a character-string. An "X" at an intersection indicates that the
symbol(s) at the top of the column can precede, in a given character-string,
the symbol(s) at the left of the row. Arguments appearing in braces indicate
that the symbols are mutually exclusive. The currency symbol is indicated by
the symbol "cs". At least one of the symbols "A " ,
"X", "Z", " 9" or "*", or at least two
of the symbols "+" , "–" or "cs" must be
present in a PICTURE string.
In Table 8-3, non-floating insertion symbols "+" and
"–" , floating insertion symbols "Z", "*",
" +", "–", and "cs", and other symbol
"P" appear twice in the PICTURE
character precedence chart. The leftmost column and uppermost row for each
symbol represents its use to the left of the decimal point position. The second
appearance of symbol in the row and column represents its use to the right of
the decimal point position.
Table 8-3: PICTURE Character Precedence Chart
| First Symbol |
Non-Floating Insertion Symbols |
Floating Insertion Symbols |
Other Symbols |
| Second Symbol |
|
B |
0 |
/ |
, |
. |
+
– |
+
– |
CR
DB |
CS |
E |
Z
* |
Z
* |
+
– |
+
– |
CS |
CS |
9 |
A
X |
S |
V |
P |
P |
G |
| Non-Floating Insertion
Symbols |
B |
x |
x |
x |
x |
x |
x |
|
|
x |
|
x |
x |
x |
x |
x |
x |
x |
x |
|
x |
|
x |
x |
| 0 |
x |
x |
x |
x |
x |
x |
|
|
x |
|
x |
x |
x |
x |
x |
x |
x |
x |
|
x |
|
x |
|
| / |
x |
x |
x |
x |
x |
x |
|
|
x |
|
x |
x |
x |
x |
x |
x |
x |
x |
|
x |
|
x |
|
| , |
x |
x |
x |
x |
x |
x |
|
|
x |
|
x |
x |
x |
x |
x |
x |
x |
|
|
x |
|
x |
|
| . |
x |
x |
x |
x |
|
x |
|
|
x |
|
x |
|
x |
|
x |
|
x |
|
|
|
|
|
|
+
– |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
+
– |
x |
x |
x |
x |
x |
|
|
|
x |
x |
x |
x |
|
|
x |
x |
x |
|
|
x |
x |
x |
|
CR
DB |
x |
x |
x |
x |
x |
|
|
|
x |
|
x |
x |
|
|
x |
x |
x |
|
|
x |
x |
x |
|
| CS |
|
|
|
|
|
x |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| E |
|
|
|
x |
x |
|
|
|
|
|
|
|
|
|
|
|
x |
|
|
x |
|
|
|
| Floating Insertion Symbols |
Z
* |
x |
x |
x |
x |
|
x |
|
|
x |
|
x |
|
|
|
|
|
|
|
|
|
|
|
|
Z
* |
x |
x |
x |
x |
x |
x |
|
|
x |
|
x |
x |
|
|
|
|
|
|
|
x |
|
x |
|
+
– |
x |
x |
x |
x |
|
|
|
|
x |
|
|
|
x |
|
|
|
|
|
|
|
|
|
|
+
– |
x |
x |
x |
x |
x |
|
|
|
x |
|
|
|
x |
x |
|
|
|
|
|
x |
|
|
|
| CS |
x |
x |
x |
x |
|
x |
|
|
|
|
|
|
|
|
x |
|
|
|
|
|
|
|
|
| CS |
x |
x |
x |
x |
x |
x |
|
|
|
|
|
|
|
|
x |
x |
|
|
|
x |
|
|
|
| Other Symbols |
9 |
x |
x |
x |
x |
x |
x |
|
|
x |
x |
x |
|
x |
|
x |
|
x |
x |
x |
x |
|
x |
|
A
X |
x |
x |
x |
|
|
|
|
|
|
|
|
|
|
|
|
|
x |
x |
|
|
|
|
|
| S |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| V |
x |
x |
x |
x |
|
x |
|
|
x |
|
x |
|
x |
|
x |
|
x |
|
x |
|
x |
|
|
| P |
x |
x |
x |
x |
|
x |
|
|
x |
|
x |
|
x |
|
x |
|
x |
|
x |
|
x |
|
|
| P |
|
|
|
|
|
x |
|
|
x |
|
|
|
|
|
|
|
|
|
x |
x |
|
x |
|
| G |
x |
|
|
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Function
The RECORD clause specifies either the number of
character positions in a fixed length record or the range of character
positions in a variable length record. If the number of character positions
varies, the clause specifies the minimum and maximum number of character
positions.
The concepts of FIXED and VARIABLE
format files
used throughout this section do not directly apply to LINE SEQUENTIAL files.
See your COBOL system documentation on file handling for details on the
implications of using LINE SEQUENTIAL files in your COBOL implementation.
Although it is a part of the standard COBOL
definition, the RECORD CONTAINS clause is explicitly excluded from the X/Open
COBOL language definitions and should not be used in a conforming X/Open COBOL
source program.
General Formats
Format 1
Format 2
Format 3
Syntax Rules
Format 1
- No record description entry for the file can specify a number of
character positions different from integer-1.
Format 2
-
Record
descriptions for the file must not describe records which contain fewer
character positions than specified by integer-2, nor records which contain a
greater number of character positions than that specified by integer-3.
-
Integer-3 must be greater than integer-2.
-
Data-name-1 must describe an elementary unsigned
integer in the Working-Storage or Linkage Section.
General Rules
All Formats
- If the RECORD clause is not specified, the size of each data record
is completely defined in the record description entry.
-
If the associated file connector is an external
file connector, all file description entries in the run unit which are
associated with that file connector must specify the same values for integer-1
or integer-2 and integer-3. If the RECORD clause is not specified, all record
description entries associated with this file connector must be the same
length.
-
Line sequential files are neither truly fixed nor
truly variable format files: the presence or absence of any RECORDING MODE,
RECORD CONTAINS or RECORD VARYING IN SIZE clause does not, therefore, impact
their performance.
Format 1
- Format 1 is used to specify fixed length records. Integer-1 specifies
the number of character positions contained in each record in the file.
Format 2
-
Format 2 is used to specify variable length
records. Integer-2 specifies the minimum number of character positions to be
contained in any record of the file. Integer-3 specifies the maximum number of
character positions in any record of the file.
-
The number of character positions associated with
a record description is determined by the sum of the number of character
positions in all elementary data items excluding redefinitions and renamings,
plus any implicit FILLER due to synchronization. If a table is specified:
- The minimum number of table elements described in the record is
used in the summation above to determine the minimum number of character
positions associated with the record description.
- The maximum number of table elements described in the record is
used in the summation above to determine the maximum number of character
positions associated with the record description.
- If integer-2 is not specified, the minimum number of character
positions to be contained in any record of the file is equal to the least
number of character positions described for a record in that file.
-
If integer-3 is not specified, the maximum number
of character positions to be contained in any record of the file is equal to
the greatest number of character positions described for a record in that file.
-
If data-name-1 is specified, the number of
character positions in the record must be placed into the data item referenced
by data-name-1 before any RELEASE, REWRITE, or WRITE statement is executed for
the file.
-
If data-name-1 is specified, the execution of a
DELETE, RELEASE, REWRITE, START, or WRITE statement or the unsuccessful
execution of a READ or RETURN statement does not alter the content of the data
item referenced by data-name-1.
-
During the execution of a RELEASE, REWRITE, or
WRITE statement, the number of character positions in the record is determined
by the following conditions:
- If data-name-1 is specified, by the content of the data item
referenced by data-name-1.
- If data-name-1 is not specified and the record does not contain a
variable occurrence data item, by the number of character positions in the
record.
- If data-name-1 is not specified and the record does contain a
variable occurrence data item, by the sum of the fixed portion and that portion
of the table described by the number of occurrences at the time of execution of
the output statement.
If the number of character positions in the logical record which is
to be written is less than integer-2 or greater than integer-3, the output
statement is unsuccessful and, except during execution of a RELEASE statement,
the associated I/O status is set to a value indicating the cause of the
condition.
-
If data-name-1 is specified, after the successful
execution of a READ or RETURN statement for the file, the contents of the data
item referenced by data-name-1 will indicate the number of character positions
in the record just read.
-
If the INTO phrase is specified in the READ or
RETURN statement, the number of character positions in the current record that
participate as the sending data items in the implicit MOVE statement is
determined by the following conditions: a.
- If data-name-1 is specified, by the content of the data item
referenced by data-name-1. b.
- If data-name-1 is not specified, by the value that would have
been moved into the data item referenced by data-name-1 had data-name-1 been
specified.
Format 3
- When format 3 of the RECORD
clause is used, integer-4 and integer-5 refer to the minimum number of
characters in the smallest size data record and the maximum number of
characters in the largest size data record respectively. However, in this case,
the size of each data record is completely defined in the record description
entry.
- The size of each data record is specified in terms of the number of
character positions required to store the logical record, regardless of the
types of characters used to represent the items within the logical record. The
size of a record is determined by the sum of the number of characters in all
fixed length elementary items plus the sum of the maximum number of characters
in any variable length item subordinate to the record. This sum can be
different from the actual size of the record. See the section Selection of
Character Representation and Radix in the chapter Concepts of the COBOL
Language, and the sections The SYNCHRONIZED Clause and The USAGE
Clause in this chapter.
Function
The RECORDING MODE clause specifies the format of the logical records in
the file.
General Formats
Format 1 (Record Sequential Files)
Format 2 (Line Sequential Files)
Format 3 (Relative and Indexed Files)
Syntax Rules
-
F and FIXED are synonyms.
-
V and VARIABLE are synonyms.
General Rules
All Formats (All Files)
- Specifying RECORDING MODE IS F causes all the records in the file to
be the same length.
Format 1 (Record Sequential Files)
-
The "U" option is documentary only.
Formats 1 and 3 (Record Sequential, Relative and Indexed
Files)
- When RECORDING MODE
IS V is specified, the records in the file can be either fixed or variable in
length. Each data record includes a record length field. These fields are not
part of the record description.
Format 2
-
Line sequential files are neither truly fixed nor
truly variable format files: the presence or absence of any RECORDING MODE,
RECORD CONTAINS or RECORD VARYING IN SIZE clause does not, therefore, impact
their performance.
Function
The REDEFINES clause allows the same computer storage area to be
described by different data description entries.
General Format
Note that level-number and data-name-1
or FILLER
are shown in the above format to improve clarity. Level-number, and
data-name-1
and FILLER
are not part of the REDEFINES clause.
Syntax Rules
- The REDEFINES clause, when specified, must immediately follow
data-name-1
or FILLER,
or it can follow the PICTURE or USAGE
clause.
- The level-numbers of data-name-1 and data-name-2 must be identical
but must not be 6 6,
78
or 88.
- This clause must not be used in level 01 entries in the File Section,
since multiple level 01 entries subordinate to an FD or SD indicator represent
implicit redefinitions of the same areas. (See General Rule 2 of the section
The DATA RECORDS Clause in this chapter.)
This clause can be used on level 01 entries in
the File Section.
- This clause must not be used in level 01 entries in the Communication
Section since multiple level 01 entries subordinate to a CD indicator represent
implicit redefinition of the same area.
-
The data description for data-name-2 can contain
a REDEFINES clause and
data-name-2 can be subordinate to an entry which contains a
REDEFINES clause.Its data description cannot contain an OCCURS clause. However,
data-name-2 can be subordinate to an item whose data description entry contains
an OCCURS clause. In this case, the reference to data-name-2 in the REDEFINES
clause cannot be subscripted or indexed. Neither the original definition nor
the redefinition can include an item whose size is variable as defined in the
OCCURS clause. (See the section The OCCURS Clause in this chapter.)
The data description for data-name-2 can contain
an OCCURS clause.
If the level number is 01, either or both of the
original definition and the redefinition can include an item whose size is
variable as defined in the OCCURS clause.
- No entry having a level-number numerically lower than the
level-number of data-name-2 and data-name-1 can occur between the data
description entries of data-name-2 and data-name-1.
-
An external or internal floating-point data item
can be the subject or object of a REDEFINES clause.
-
Data-name-2 must not be qualified even if it is
not unique since no ambiguity of reference exists in this case because of the
required placement of the REDEFINES clause within the source program.
Data-name-2 may be qualified but any
qualification specified is ignored.
- The entries giving the new description of the character positions
must not contain any VALUE clauses except in condition-name entries.
General Rules
- Redefinition starts at data-name-2 and ends when a level-number less
than or equal to that of data-name-2 is encountered.
- When the level-number of data-name-1 is other than 01, it must
specify the same number of character positions that the data item referenced by
data-name-2 contains
except that the data-name-1 area can be either
smaller than the data-name-2 area
or be larger than the data- name-2 area. In this
case, extra storage is reserved to provide sufficient storage for the number of
character positions in the largest of the redefining or redefined items.
It is important to observe that the REDEFINES clause specifies the
redefinition of a storage area, not of the data items occupying the area.
- Multiple redefinitions of the same character positions are permitted.
The entries giving the new descriptions of the character positions must follow
the entries defining the area being redefined, without intervening entries that
define new character positions. Multiple redefinitions of the same character
positions must all use the data-name of the entry that originally defined the
area
or the data-name of any other preceding
redefinition of that entry.
- Multiple level 01 entries subordinate to any given level indicator
(FD, CD or SD) represent implicit redefinitions of the same area.
Function
The RENAMES clause permits alternative, possibly overlapping, groupings
of elementary items.
General Format
Level-number 66 and data-name-1 are shown in the above format to improve
clarity. Level-number and data-name-1 are not part of the RENAMES clause.
Syntax Rules
- Any number of RENAMES entries can be written for a logical record.
- All RENAMES entries referring to data items within a given logical
record must immediately follow the last data description entry of the
associated record description entry.
- Data-name-2 and data-name-3 must be names of elementary items or
groups of elementary items in the same logical record, and cannot be the same
data-name. A 66 level entry cannot rename another 66 level entry, nor can it
rename a 77,
78,
88, or 01 entry.
A 66 level entry may rename another 66 level
entry or a level 77 or level 01 entry.
- Data-name-1 cannot be used as a qualifier, and can be qualified only
by the names of the associated level 01, FD, CD or SD entries. Neither
data-name-2 nor data-name-3 can have an OCCURS clause in its data description
entry, nor be subordinate to an item that has an OCCURS clause in its data
description entry. (See the section The OCCURS Clause.)
- The beginning of the area described by data-name-3 must not be to the
left of the beginning of the area described by data-name-2. The end of the area
described by data-name-3 must be to the right of the end of the area described
by data-name-2. Data-name-3, therefore, cannot be subordinate to data-name-2.
- Data-name-2 and data-name-3 can be qualified.
- The words THRU and THROUGH are equivalent.
- None of the items within the range, including data-name-2 and
data-name-3, if specified, can be an item whose size is variable as defined in
the section The OCCURS Clause in this chapter.
General Rules
- When data-name-3 is specified, data-name-1 is a group item which
includes all elementary items starting with data-name-2 (if data-name-2 is an
elementary item) or the first elementary item in data-name-2 (if data-name-2 is
a group item), and concluding with data-name-3 (if data-name-3 is an elementary
item) or the last elementary item in data-name-3 (if data-name-3 is a group
item).
- When data-name-3 is not specified, all of the attributes of
data-name-2 become the data attributes for data-name-1.
-
When data-name-2 and data-name-3 are not
explicitly qualified and when no ambiguity of reference exists, implied
qualification of the 01 level item is used.
Function
The SIGN clause specifies the position and the mode of representation of
the operational sign when it is necessary to describe these properties
explicitly.
General Format
Syntax Rules
- The SIGN clause can be specified only for a numeric data description
entry whose PICTURE contains the character "S" , or a group item
containing at least one such numeric data description entry.
- The numeric data description entries to which the SIGN clause applies
must be described, implicitly or explicitly, as USAGE IS DISPLAY.
- At most one SIGN clause can apply to any given numeric data
description entry.
This rule is removed.
- If the CODE-SET clause is specified, any signed numeric data
description entries associated with that file description entry must be
described with the SIGN IS SEPARATE clause.
This restriction is not enforced. See the
section The CODE-SET Clause in this chapter.
General Rules
- The optional SIGN clause, if present, specifies the position and the
mode of representation of the operational sign for the numeric data description
entry to which it applies, or for each numeric data description entry
subordinate to the group to which it applies. The SIGN clause applies only to
numeric data description entries whose PICTURE contains the character
"S"; the "S" indicates the presence of, but neither the
representation nor, necessarily, the position of the operational sign.
- A numeric data description entry whose PICTURE contains the character
"S", but to which no optional SIGN clause applies, has an operational
sign, but neither the representation nor, necessarily, the position of the
operational sign is specified by the character "S". In this (default)
case, General Rules 3 through 5 do not apply to such signed numeric data items.
The representation of the default operational sign is defined in the section
Selection Of Character Representation And Radix in the chapter
Concepts of the COBOL Language.
- If the optional SEPARATE CHARACTER phrase is not present, then:
- the operational sign will be presumed to be associated with the
leading (or, respectively, trailing) digit position of the elementary numeric
data item in a manner defined in the section Selection Of Character
Representation And Radix in the chapter Concepts of t