HP OpenVMS Systems Documentation

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3. Close file
   The file is closed.

4. Reel/unit removal
   The current reel rewinds and is logically removed from the run unit However, the run unit can access the reel again in its proper order of reels in the file. To do this, the executable image must subsequently execute the following:
   • A CLOSE statement without the REEL/UNIT phrase for the file
   • An OPEN statement for the file

5. File lock
   The executable image cannot open the file again in its current execution.

6. Close reel/unit
   For input and input-output files, if the current reel is the last or only reel for the file:
   • A reel swap does not occur.
   • The Current Volume Pointer remains the same.
   • The File Position Indicator denotes that there is no next logical record.
   
   If another reel follows the current reel for the file:
   • A reel swap occurs.
   • The Current Volume Pointer points to the next reel for the file.
   • The File Position Indicator points to the next record in the file. If there are no records for the current volume, another reel swap occurs.
   
   For output files (reel/unit media), a reel swap occurs. The Current Volume Pointer points to the new reel.
   Executing the next WRITE statement for the file transfers a logical record to the new reel of the file.
   For output files (nonreel/unit media), execution of this statement is considered successful. The file remains in the open mode and no action takes place, except as specified in General Rule 2.

7. Rewind
   The current reel (or device) is positioned to its physical beginning.

8. Optional phrases ignored
   The CLOSE statement is executed as if none of the optional phrases are present.

24. Invalid
    This is an invalid combination of CLOSE option and file category. It results in FILE STATUS data item value 30.

Technical Note

CLOSE statement execution can result in these FILE STATUS data item values:

Additional Reference

See Section 6.6.8, I-O Status for more information.

6.8.7 COMPUTE

Function

The COMPUTE statement evaluates an arithmetic expression and stores the result in one or more data items.

rsult

is the identifier of an elementary numeric item or elementary numeric edited item. It is the resultant identifier.

arithmetic-expression

is an expression as described in Section 6.4, Arithmetic Expressions.

stment

is an imperative statement executed when a size error condition has occurred.

stment2

is an imperative statement executed when no size error condition has occurred.

General Rules

1. The arithmetic expression is evaluated. Its value then replaces the current value of each occurrence of rsult, from left to right.
2. If the arithmetic-expression consists of a single identifier or literal, the COMPUTE statement behaves like a MOVE statement with the single identifier or literal acting as the source operand and each result operand acting as a destination operand.
3. For any rsult specification that includes the word rounded, the value of the expression is rounded before being moved to rsult.

Additional References

• Section 6.1.4, Scope of Statements
• Section 6.6.1, Arithmetic Operations
• Section 6.6.2, Multiple Receiving Fields in Arithmetic Statements
• Section 6.6.3, ROUNDED Phrase
• Section 6.6.4, ON SIZE ERROR Phrase
• Section 6.6.7, Overlapping Operands and Incompatible Data

Examples

Each of the examples assume these data descriptions and initial values:

INITIAL VALUES

03  ITEMA  PIC 999V99 VALUE 2.                      2.00
03  ITEMB  PIC 999V99 VALUE 3.                      3.00
03  ITEMC  PIC 999V99 VALUE 4.                      4.00
03  ITEMD  PIC 999V99 VALUE 5.                      5.00

RESULTS

1. No rounding:

   COMPUTE ITEMC = ITEMC = 2.82 (ITEMA + 6) ** (.1 * ITEMD).

2. With rounding:

   COMPUTE ITEMC ROUNDED = ITEMC = 2.83 (ITEMA + 6) ** (.1 * ITEMD).

3. The ON SIZE ERROR phrase:

   COMPUTE ITEMB = (ITEMA * ITEMD) ** 3 ITEMB = 3.00 ON SIZE ERROR MOVE 100 TO ITEMC. ITEMC = 100.00

4. The NOT ON SIZE ERROR phrase:

   COMPUTE ITEMB = (ITEMA * ITEMD) ** 2 ITEMB = 100.00 ON SIZE ERROR MOVE 100 TO ITEMC NOT ON SIZE ERROR MOVE 200 TO ITEMC. ITEMC = 200.00

Function

The CONTINUE statement indicates that no executable statement is present. It causes an implicit control transfer to the next executable statement.

Syntax Rule

The CONTINUE statement can be used wherever a conditional or imperative statement can be used.

General Rule

The CONTINUE statement causes an implicit control transfer to the next executable statement.

Example

READ FILE-A
  INVALID KEY
    CONTINUE.
MOVE ...

This example shows how CONTINUE can replace an INVALID KEY imperative statement. Control passes to the MOVE statement whether or not the INVALID KEY condition occurs.

6.8.9 DELETE

Function

The DELETE statement logically removes a record from a mass storage file.

file-name

is the name of a relative or indexed file described in the Data Division. It cannot be the name of a sequential or line sequential file or a sort or merge file.

stment

is one or more imperative statements executed for an invalid key condition.

stment2

is one or more imperative statements executed for a not invalid key condition.

Syntax Rules

1. There cannot be an INVALID KEY phrase or a NOT INVALID KEY phrase for a DELETE statement that references a file in sequential access mode.
2. There must be an INVALID KEY phrase if: (a) the file is not in sequential access mode and (b) there is no applicable USE AFTER EXCEPTION procedure.

General Rules

1. The file must be open in I-O mode when the DELETE statement executes.
2. For a file in sequential access mode, a successfully executed READ statement must be the last input-output statement executed for the file before the DELETE statement. The I/O system logically removes the record that the READ statement accessed.
3. For a relative file in random or dynamic access mode, the I/O system logically removes the record identified by the file's RELATIVE KEY data item. If the file does not contain that record, an invalid key condition exists.
4. For an indexed file in random access mode, the I/O system (logically removes the record identified by the file's primary record key data item. If the file does not contain that record, an invalid key condition exists.
5. For an indexed file in dynamic access mode, the behavior depends on the DUPLICATES phrase of the RECORD KEY clause of the SELECT statement. If the primary key allows duplicates, Rule 2 applies. If the primary key does not allow duplicates, Rule 4 applies.
6. After successful DELETE statement execution, the identified record has been logically removed from the file. It is no longer accessible.
7. DELETE statement execution does not affect the contents of the record area. It also does not affect the contents of the data item referred to in the DEPENDING ON phrase of the file's RECORD clause.
8. For sequential access files, DELETE statement execution does not affect the File Position Indicator.
9. For dynamic access files, the File Position Indicator can point to the record to be deleted before the DELETE statement executes. In this case, once the DELETE statement executes, the File Position Indicator:
   • Points to a relative file's next existing record
   • Points to an indexed file's next existing record, as established by the Key of Reference
   • Indicates the at end condition if the file has no next record
   
   In all other cases, the File Position Indicator is not affected by the execution of a DELETE statement.
10. DELETE statement execution updates the value of the FILE STATUS data item for the file.
11. If there is an applicable USE AFTER EXCEPTION procedure, it executes whenever an input or output condition occurs that would result in a nonzero value in the first character of a FILE STATUS data item. However, it does not execute if the condition is invalid key, and there is an INVALID KEY phrase. If the condition is not invalid key and no applicable USE AFTER EXCEPTION Declarative procedure exists, the run unit terminates abnormally.