Procedure Division (cont.) [ COBOL/HP-UX Language Reference for the Series 700 and 800 ] MPE/iX 5.0 Documentation
COBOL/HP-UX Language Reference for the Series 700 and 800
Procedure Division (cont.)
The STOP Statement
Function
The STOP statement causes a permanent or temporary suspension of the
execution of the object program.
________________________________________________________________________
|(ANS85) |
|The STOP literal statement 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 |
________________________________________________________________________
________________________________________________________________________
|(MF) |
|All dialects within this COBOL implementation fully support this |
|syntax. Refer to your COBOL System Reference for details on |
|using the FLAGSTD directive to detect all occurrences of this |
|syntax. |
________________________________________________________________________
________________________________________________________________________
|(XOPEN) |
|Although it is a part of the standard COBOL definition, the Stop |
|literal format is explicitly excluded from the X/Open COBOL language |
|definitions and should not be used in an X/Open COBOL conforming |
|source program. |
________________________________________________________________________
General Format
Format 1
Syntax Rules
Format 1
1. Literal can be numeric or nonnumeric or can be any figurative
constant, except ALL.
2. If literal is numeric, then it must be an unsigned integer.
________________________________________________________________________
|A signed integer is allowed. (OSVS) (VSC2) |
________________________________________________________________________
Formats 1 and 2
3. If a STOP RUN statement appears in a consecutive sequence of
imperative statements within a sentence, it must appear as the last
statement in that sequence.
________________________________________________________________________
|(OSVS) (VSC2) (MF) |
|The STOP RUN statement does not have to be the last statement in a |
|sequence, but any statements following the STOP RUN in such a sequence|
|will not be executed. |
________________________________________________________________________
________________________________________________________________________
|(MF) |
| |
|Format 2 |
| |
| |
| |
|4. Literal-1 must be an integer. |
| |
|5. Data-name-1 can be specified anywhere within the Data Division. |
| |
|6. The SIZE clause defines the number of bytes to be passed. The |
| value is passed in COMP-5 format. |
| |
|7. If the SIZE clause is present, literal-2 must be numeric. |
| |
________________________________________________________________________
General Rules
Format 1
1. If the RUN phrase is specified, execution of the run unit ceases
and control is transferred to the operating system.
2. If STOP literal is specified, the literal is communicated to the
operator. Continuation of the object program begins with the
execution of the next executable statement in sequence.
________________________________________________________________________
|(MF) Pressing the Enter key or equivalent continues execution. |
________________________________________________________________________
________________________________________________________________________
|(MF) |
| |
|Format 2 |
| |
| |
| |
|3. The size of the GIVING fields is limited to four bytes. Specific|
| operating systems or COBOL implementations can have different |
| limits. See your COBOL System Reference for additional |
| information. |
| |
|4. For a system in which COMP-5 fields are stored in "reverse order"|
| an implicit (invisible to the program/programmer) move will occur|
| from an implicit COMP-5 item to a receiving binary field |
| upon program entry when a BY VALUE phrase is specified in |
| either a PROCEDURE USING or an ENTRY USING statement if |
| the VALUE field is defined as BINARY, COMP, COMP-4, or |
| COMP-X. |
| |
|5. GIVING items are not affected by the RTNCODE-SIZE directive. |
| |
|6. It is the programmer's responsibility to ensure that fields |
| referenced in a BY VALUE phrase agree as to size and usage in |
| both the calling and called program. In cases where these rules |
| are violated, results are unpredictable. However, there will be |
| no compile-time verification of this. |
| |
| In cases such as COMP-5 and Pointer data items where, in |
| some COBOL systems, they are implicitly identical storage |
| definitions in the current implementation, mixing these different|
| usages in the calling and called programs may currently |
| give the desired results, but upward compatibility is not |
| guaranteed. |
| |
________________________________________________________________________
The STRING Statement
Function
The STRING statement provides juxtaposition of the partial or complete
contents of two or more data items into a single data item.
General Format
Syntax Rules
1. Each literal can be any figurative constant without the optional
word ALL.
2. All literals must be described as nonnumeric literals, and all
identifiers, except identifier-4, must be described implicitly or
explicitly as USAGE IS DISPLAY.
3. Identifier-3 must represent an elementary alphanumeric data item
without editing symbols or the JUSTIFIED clause.
4. Identifier-4 must represent an elementary numeric integer data
item of sufficient size to contain a value equal to the size plus
1 of the area referenced by identifier-3. The "P" can not be used
in the PICTURE character-string of identifier-4.
5. Where identifier-1 or identifier-2 is an elementary numeric data
item, it must be described as an integer without the symbol "P" in
its PICTURE character-string.
________________________________________________________________________
|(MF) |
| |
| |
| |
|6. Identifier-3 must not be reference modified. |
| |
________________________________________________________________________
General Rules
1. Identifier-1, or literal-1, represents the sending item.
Identifier-3 represents the receiving item.
2. Literal-2, identifier-2, indicate the character(s) delimiting the
move. If the SIZE phrase is used, the complete data item defined
by identifier-1, or literal-1, is moved. When a figurative
constant is used as the delimiter, it stands for a single
character nonnumeric literal.
3. When a figurative constant is specified as literal-1, or
literal-2, it refers to an implicit one-character data item whose
usage is DISPLAY.
4. When the STRING statement is executed, the transfer of data is
governed by the following rules:
a. Those characters from literal-1, or from the contents of
the data item referenced by identifier-1, are transferred
to the contents of identifier-3 in accordance with the
rules for alphanumeric to alphanumeric moves, except that
no space filling will be provided. (See the section "The
MOVE Statement" earlier in this chapter.)
b. If the DELIMITED phrase is specified without the SIZE
phrase, the contents of the data item referenced by
identifier-1, or the value of literal-1, is transferred to
the receiving data item in the sequence specified in the
STRING statement beginning with the leftmost character and
continuing from left to right until the end of the data
item is reached, or until the character(s) specified by
literal-2, or by the contents of identifier-2 are
encountered. The character(s) specified by literal-2, or
by the data item referenced by identifier-2 are not
transferred.
c. If the DELIMITED phrase is specified with the SIZE phrase,
the entire contents of literal-1, or the contents of the
data item referenced by identifier-1, are transferred, in
the sequence specified in the STRING statement, to the data
item referenced by identifier-3 until all data has been
transferred or the end of the data item referenced by
identifier-3 has been reached.
5. If the POINTER phrase is specified, identifier-4 is explicitly
available to the programmer, who is then responsible for setting
its initial value. The initial value must not be less than one.
6. If the POINTER phrase is not specified, the following General
Rules apply as if the user had specified identifier-4 with an
initial value of 1.
7. When characters are transferred to the data item referenced by
identifier-3, the moves behave as though the characters were moved
one at a time from the source into the character position of the
data item referenced by identifier-3 designated by the value
associated with identifier-4, and then identifier-4 was increased
by one prior to the move of the next character. The value
associated with identifier-4 is changed during execution of the
STRING statement only by the behavior specified above.
8. At the end of execution of the STRING statement, only the portion
of the data item referenced by identifier-3 that was referenced
during the execution of the STRING statement is changed. All
other portions of the data item referenced by identifier-3 will
contain data that was present before this execution of the STRING
statement.
9. Before each move of a character to the data item referenced by
identifier-3, if the value associated with the data item
referenced by identifier-4 is either less than one or exceeds the
number of character positions in the data item referenced by
identifier-3, no (further) data is transferred to the data item
referenced by identifier-3, and the NOT ON OVERFLOW phrase, if
specified, is ignored (ANS85) and control is transferred to the
end of the STRING statement or, if the ON OVERFLOW phrase is
specified, to imperative- statement-1. If control is transferred
to imperative- statement-1, execution continues according to the
rules for each statement specified in imperative-statement-1. If
a procedure branching or conditional statement which causes
explicit transfer of control is executed, control is transferred
in accordance with the rules for that statement; otherwise, upon
completion of the execution of imperative-statement-1, control is
transferred to the end of the STRING statement.
________________________________________________________________________
|(ANS85) |
| |
| |
| |
|10. If, at the time of execution of a STRING statement with the NOT |
| ON OVERFLOW phrase, the conditions described in General Rule 9 |
| are not encountered, after completion of the transfer of data |
| according to the other general rules, the ON OVERFLOW phrase, if |
| specified, is ignored and control is transferred to the end of |
| the STRING statement or, if the NOT ON OVERFLOW phrase |
| is specified, to imperative- statement-2. If control is |
| transferred to imperative- statement-2, execution continues |
| according to the rules for each statement specified in |
| imperative-statement-2. If a procedure branching or conditional |
| statement which causes explicit transfer of control is executed, |
| control is transferred in accordance with the rules for that |
| statement; otherwise, upon completion of the execution of |
| imperative-statement-2, control is transferred to the end of the |
| STRING statement. |
| |
|11. The END-STRING phrase delimits the scope of the STRING statement.|
| (See the section "Explicit and Implicit Scope Terminators" in|
| the chapter COBOL Concepts.) |
| |
________________________________________________________________________
The SUBTRACT Statement
Function
The SUBTRACT statement is used to subtract one, or the sum of two or
more, numeric data items from one or more items, and set the values of
one or more items equal to the results.
General Formats
Format 1
Format 2
Format 3
Syntax Rules
1. Each identifier must refer to a numeric elementary item, except
that in Format 2 each identifier following the word GIVING must
refer to either an elementary numeric item or an elementary
numeric edited item, and in Format 3 each identifier must refer to
a group item.
2. Each literal must be a numeric literal.
3. The composite of operands must not contain more than 18 digits.
(See the section "Arithmetic Statements" earlier in this
chapter.)
a. In Format 1 the composite of operands is determined by
using all of the operands in a given statement.
b. In Format 2 the composite of operands is determined by
using all of the operands in a given statement excluding
the data items that follow the word GIVING.
c. In Format 3 the composite operands is determined separately
for each pair of corresponding data items.
4. CORR is an abbreviation for CORRESPONDING.
________________________________________________________________________
|(OSVS) (VSC2) (MF) |
| |
| |
| |
|5. Floating-point data items and literals can be used anywhere |
| numeric data items and literals can be specified. |
| |
________________________________________________________________________
General Rules
1. See the sections "The ROUNDED Phrase" , "
The ON SIZE ERROR Phraseand NOT ON SIZE ERROR Phrase (ANS85)" ,
"Arithmetic Statements" , "Overlapping Operands" and
"Multiple Results in Arithmetic Statements" in this chapter.
2. In Format 1, all literals or identifiers preceding the word FROM
are added together and this total is subtracted from the current
value of identifier-2 storing the result immediately into
identifier-2, and repeating this process respectively for each
operand following the word FROM.
3. In Format 2, all literals or identifiers preceding the word FROM
are added together, the sum is subtracted from literal-2 or
identifier-2 and the result of the subtraction is stored as the
new value of each data item referenced by identifier-3.
4. If Format 3 is used, data items in identifier-1 are subtracted
from and stored into corresponding data items in identifier-2.
________________________________________________________________________
|(MF) (VSC2) |
| |
| |
| |
|5. The COBOL system ensures enough places are carried so as not to |
| lose significant digits during execution. |
| |
________________________________________________________________________
________________________________________________________________________
|The TRANSFORM Statement |
| |
|(OSVS) |
| |
|Function |
| |
|The TRANSFORM statement is used to alter characters according to a |
|transformation rule. |
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General Format
________________________________________________________________________
|(OSVS) |
| |
|Syntax Rules |
| |
| |
| 1. Identifier-3 can be any elementary item except a numeric item |
| with USAGE other than DISPLAY, or a group item. |
| |
| 2. Identifier-1 and identifier-2 should be elementary alphabetic |
| or alphanumeric items. |
| |
| 3. Nonnumeric-literal-2 or identifier-2 must be either one |
| character long or the same length as nonnumeric-literal-1 or |
| identifier-1. |
| |
|General Rules |
| |
| |
| 1. The use of figurative-constant-1 and/or figurative-constant-2 |
| is equivalent to the use of a single-character nonnumeric- |
| literal with the same value. |
| |
| 2. If either identifier-1 or identifier-2 references the same |
| computer storage area as identifier-3, the result of the |
| TRANSFORM is undefined. (See the section "The REDEFINES |
| Clause" earlier in this chapter.) |
| |
| 3. If characters are repeated in nonnumeric-literal-1 or |
| identifier-1, then the result of the TRANSFORM operation is |
| undefined. |
| |
| 4. Execution of the TRANSFORM statement scans identifier-3 for |
| occurrences of individual characters from identifier-1 |
| or nonnumeric-literal-1. When a match is found, the |
| corresponding character (or the single character of a |
| one-character field) from identifier-2 or nonnumeric-literal-2 |
| is substituted into that character position in identifier-3. |
| The correspondence between identifier-1 or nonnumeric- |
| literal-1 and identifier-2 or nonnumeric-literal-2 is by |
| occurrence number of the character within the data item |
| (starting from the left). |
________________________________________________________________________
The UNSTRING Statement
Function
The UNSTRING statement causes contiguous data in a sending field to be
separated and placed into multiple receiving fields.
General Format
Syntax Rules
1. Each literal must be a nonnumeric literal. In addition, each
literal can be any figurative constant without the optional word
ALL.
2. Identifier-1, identifier-2, identifier-3, and identifier-5 must be
described, implicitly or explicitly, as an alphanumeric data-
item.
3. Identifier-4 can be described as either alphabetic (except that
the symbol "B" can not be used in the PICTURE character-string),
alphanumeric, or numeric (except that the symbol "P" can not be
used in the PICTURE character-string), and must be described as
USAGE IS DISPLAY.
________________________________________________________________________
|(MF) |
| |
| |
| |
|4. Syntax Rules 2 and 3 do not apply. Instead, the following rules |
| apply: |
| |
| |
| * Identifier-1 must be alphanumeric |
| |
| * Identifier-2 and identifier-3 must be USAGE DISPLAY and |
| must not be edited |
| |
| * Identifier-4 and identifier-5 must be USAGE DISPLAY |
| |
| * Identifier-4 can have any USAGE if it is defined |
| as numeric and the data results in a valid move |
| operation |
| |
________________________________________________________________________
________________________________________________________________________
|(OSVS) (VSC2) (MF) |
| |
| |
| |
|5. Identifier-4 must not be defined as a floating-point item. |
| |
________________________________________________________________________
6. Identifier-6 and identifier-8 must reference integer data items,
(except that the symbol "P" can not be used in the PICTURE
character-string).
7. Identifier-1 must be described as an elementary numeric integer data
item of sufficient size to contain a value equal to 1 plus the size
of the data item referenced by identifier-1. The symbol "P" can not
be used in the PICTURE character string of identifier-7.
8. No identifier can name a level 88 entry.
9. The DELIMITER IN phrase and the COUNT IN phrase can be specified
only if the DELIMITED BY phrase is specified.
General Rules
1. All references to identifier-2, literal-1, apply equally to
identifier-3, literal-2, respectively and all recursions thereof.
2. Identifier-1 represents the sending area.
3. Identifier-4 represents the data receiving area. Identifier-5
represents the receiving area for delimiters.
4. Literal-1 or the data item referenced by identifier-2 specifies a
delimiter.
5. The data item referenced by identifier-6 represents the count of
the number of characters within the data item referenced by
identifier-1 isolated by the delimiters for the move to the data
item referenced by identifier-4. This value does not include a
count of the delimiter character(s).
6. The data item referenced by identifier-7 contains a value that
indicates a relative character position within the area defined by
identifier-1.
7. The data item referenced by identifier-8 is a counter that records
the number of data items acted upon during the execution of an
UNSTRING statement.
8. When a figurative constant is used as the delimiter, it stands for
a single character nonnumeric literal.
When the ALL phrase is specified, one occurrence or two or more
contiguous occurrences of literal-1 (figurative constant or not)
or the contents of the data item referenced by identifier-2 are
treated as if it were only one occurrence, and this occurrence is
moved to the receiving data item according to the rules in General
Rule 13d.
9. When any examination encounters two contiguous delimiters, the
current receiving area is either space or zero filled according to
the description of the receiving area.
10. Literal-1 or the contents of the data item referenced by
identifier-2 can contain any character in the computer's character
set.
11. Each literal-1 or the data item referenced by identifier-2
represents one delimiter. When a delimiter contains two or more
characters, all of the characters must be present in contiguous
positions of the sending item and in the order given, to be
recognized as a delimiter.
12. When two or more delimiters are specified in the DELIMITED BY
phrase, an "OR" condition exists between them. Each delimiter is
compared to the sending field. If a match occurs, the
character(s) in the sending field is considered to be a single
delimiter. No character(s) in the sending field can be considered
a part of more than one delimiter.
Each delimiter is applied to the sending field in the sequence
specified in the UNSTRING statement.
13. When the UNSTRING statement is initiated, the current receiving
area is the data item referenced by identifier-4. Data
transferred from the data item referenced by identifier-1 to the
data item referenced by identifier-4 according to the following
rules:
a. If the POINTER phrase is specified, the string of
characters referenced by identifier-1 is examined beginning
with the relative character position indicated by the
contents of the data item referenced by identifier-7. If
the POINTER phrase is not specified, the string of
characters is examined beginning with the leftmost
character position.
b. If the DELIMITED BY phrase is specified, the examination
proceeds left to right until either a delimiter specified
by the value of literal-1 or the data item referenced by
identifier-2 is encountered. (See General Rule 11.) If
the DELIMITED BY phrase is not specified, the number of
characters examined is equal to the size of the current
receiving area. However, if the sign of the receiving item
is defined as occupying a separate character position, the
number of characters examined is one less than the size of
the current receiving area.
If the end of the data item referenced by identifier-1 is
encountered before the delimiting condition is met, the
examination terminates with the last character examined.
c. The characters thus examined (excluding the delimiting
character(s), if any) are treated as an elementary
alphanumeric data item, and are moved into the current
receiving area according to the rules for the MOVE
statement. (See the section "The MOVE Statement"
earlier in this chapter.)
d. If the DELIMITER IN phrase is specified, the delimiting
character(s) are treated as an elementary alphanumeric data
item and are moved into the data item referenced by
identifier-5 according to the rules for the MOVE statement.
(See the section "The MOVE Statement" earlier in this
chapter.) If the delimiting condition is the end of the
data item referenced by identifier-1, then the data item
referenced by identifier-5 is space-filled.
e. If the COUNT IN phrase is specified, a value equal to the
number of characters thus examined (excluding the delimiter
character(s) if any) is moved into the area referenced by
identifier-6 according to the rules for an elementary move.
f. If the DELIMITED BY phrase is specified the string of
characters is further examined beginning with the first
character to the right of the delimiter. If the DELIMITED
BY phrase is not specified, the string of characters is
further examined beginning with the character to the right
of the last character transferred.
g. After data is transferred to the data item referenced by
identifier-4, the current receiving area is the data item
referenced by the next recurrence of identifier-4. The
behavior described in paragraph 13b. through 13f. is
repeated until either all the characters are exhausted in
the data item referenced by identifier-1, or until there
are no more receiving areas.
14. The initialization of the contents of the data items associated
with the POINTER phrase or the TALLYING phrase is the
responsibility of the user.
15. The contents of the data item referenced by identifier-7 will be
incremented by one for each character examined in the data item
referenced by identifier-1. When the execution of an UNSTRING
statement with a POINTER phrase is complete, the contents of the
data item referenced by identifier-7 will contain a value equal to
the initial value plus the number of characters examined in the
data item referenced by identifier-1.
16. When the execution of an UNSTRING statement with a TALLYING phrase
is completed, the contents of the data item referenced by
identifier-8 contains a value equal to its initial value plus the
number of data receiving items acted upon.
17. Either of the following situations causes an overflow condition:
a. An UNSTRING is initiated, and the value in the data item
referenced by identifier-7 is less than 1 or greater than
the size of the data item referenced by identifier-1.
b. If, during execution of an UNSTRING statement, all data
receiving areas have been acted upon, and the data item
referenced by identifier-1 contains characters that have
not been examined.
18. When an overflow condition exists, the UNSTRING operation is
terminated, the NOT ON OVERFLOW phrase, if specified, is ignored
and (ANS85) control is transferred to the end of the UNSTRING
statement or, if the ON OVERFLOW phrase is specified, to
imperative-statement-1. If control is transferred to
imperative-statement-1, execution continues according to the rules
for each statement specified in imperative-statement-1. If a
procedure branching or conditional statement which causes explicit
transfer of control is executed, control is transferred in
accordance with the rules for that statement; otherwise, upon
completion of the execution of imperative-statement-1, control is
transferred to the end of the UNSTRING statement.
________________________________________________________________________
|(ANS85) |
| |
| |
| |
|19. The END-UNSTRING phrase delimits the scope of the UNSTRING |
| statement. (See the section "Explicit and Implicit Scope |
| Terminators" in the chapter COBOL Concepts.) |
| |
________________________________________________________________________
20. If, at the time of execution of an UNSTRING statement, the
conditions described in General Rule 17 are not encountered, after
completion of the transfer of data according to the other general
rules, the ON OVERFLOW phrase, if specified, is ignored and control
is transferred to the end of the UNSTRING statement
________________________________________________________________________
|(ANS85) |
|or, if the NOT ON OVERFLOW phrase is specified, to |
|imperative-statement-2. If control is transferred to imperative- |
|statement-2, execution continues according to the rules for each |
|statement specified in imperative-statement-2. If a procedure |
|branching or conditional statement which causes explicit transfer of |
|control is executed, control is transferred in accordance with the |
|rules for that statement; otherwise, upon completion of the execution |
|of imperative-statement-2, control is transferred to the end of the |
|UNSTRING statement. |
________________________________________________________________________
21. The evaluation of subscription and indexing for the identifiers is
as follows:
a. Any subscripting or indexing associated with identifier-1,
identifier-7, identifier-8 is evaluated only once,
immediately before any data is transferred as the result of
the execution of the UNSTRING statement.
b. Any subscripting or indexing associated with identifier-2,
identifier-3, identifier-4, identifier-5, identifier-6 is
evaluated immediately before the transfer of data into the
respective data item.
________________________________________________________________________
|(ANS85) |
| |
| |
| |
|22. Any subscripting associated with the DELIMITED BY identifier, the|
| INTO identifier, the DELIMITER IN identifier, or the COUNT IN |
| identifier is evaluated once, immediately before the examination |
| of the sending fields for the delimiter. |
| |
________________________________________________________________________
23. If identifier-1, identifier-2 or identifier-3, occupies the same
storage area as identifier-4, identifier-5 , identifier-6 ,
identifier-7 or identifier-8, or if identifier-4, identifier-5 or
identifier-6, occupies the same storage area as identifier-7 or
identifier-8, or if identifier-7 and identifier-8 occupy the same
storage area, the result of the execution of this statement is
undefined, even if they are defined by the same data description
entry.
________________________________________________________________________
|The USE Statement |
| |
|(ANS85) |
| |
|Function |
| |
|The USE statement determines whether the associated declarative |
|procedures are invoked during the execution of any program contained |
|within the program which includes the USE statement. |
| |
|The BEFORE REPORTING format determines whether the associated |
|declarative procedures are invoked during the execution of any program|
|contained within the program which includes the USE BEFORE REPORTING |
|statement. |
________________________________________________________________________
General Formats
Format 1
________________________________________________________________________
|(ANS85) |
| |
|Format 2 |
| |
| USE [GLOBAL] BEFORE REPORTING identifier-1 |
| |
|Syntax Rules |
| |
|Format 1 |
| |
|See Chapter 5 , File Input And Output . |
| |
|General Rule |
| |
|Special precedence rules are followed when programs are contained |
|within other programs. In applying these rules, only the first |
|qualifying declarative will be selected for execution. The |
|declarative which is selected for execution must satisfy the rules for|
|execution of that declarative. The order of precedence for selecting |
|a declarative is: |
| |
| |
| a. The declarative within the program that contains the statement |
| which caused the qualifying condition. |
| |
| b. The declarative in which the GLOBAL phrase is specified and |
| which is within the program directly containing the program |
| which was last examined for a qualifying declarative. |
| |
| c. Any declarative selected by applying rule 1b. to each more |
| inclusive containing program until rule 1b. is applied to the |
| outermost program. If no qualifying declarative is found, none|
| is executed. |
________________________________________________________________________
MPE/iX 5.0 Documentation