Compaq COBOL AAQ2G1FTK - Manual (Page 11)

13.3.1 OpenVMS Alpha Run-Time Library Routines . . . . . . . . . . . . . . . . . . . 13–4
13.3.2 System Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–4
13.4 Calling Routines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–5
13.4.1 Determining the Type of Call (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . 13–5
13.4.2 Defining the Argument (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–6
13.4.3 Calling the External Routine (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . 13–7
13.4.4 Calling System Routines (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . 13–8
13.4.4.1 System Routine Arguments (OpenVMS) . . . . . . . . . . . . . . . . . . . . 13–8
13.4.4.2 Calling a System Routine in a Function Call (OpenVMS) . . . . . . . 13–11
13.4.4.3 Calling a System Routine in a Procedure Call (OpenVMS) . . . . . . 13–13
13.4.5 Checking the Condition Value (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . 13–13
13.4.5.1 Library Return Status and Condition Value Symbols
(OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13–15
13.4.6 Locating the Result (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–15
13.5 Establishing and Removing User Condition Handlers (OpenVMS) . . . . . . 13–15
13.6 Examples (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–19
14 Using the REFORMAT Utility
14.1 Running the REFORMAT Utility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14–1
14.2 ANSI-to-Terminal Format Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14–2
14.3 Terminal-to-ANSI Format Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14–3
14.4 REFORMAT Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14–4
15 Optimizing Your Compaq COBOL Program
15.1 Specifying Optimization on the Compiler Command Line . . . . . . . . . . . . . 15–1
15.2 Specifying Alignment of Data for Optimum Performance . . . . . . . . . . . . . 15–5
15.3 Using COMP Data Items for Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–5
15.4 Other Ways to Improve the Performance of Operations on Numeric
Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15–7
15.4.1 Mixing Scale Factors and Data Types . . . . . . . . . . . . . . . . . . . . . . . . . 15–7
15.4.2 Limiting Significant Digits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–7
15.4.3 Reducing the Compexity of Arithmetic Expressions . . . . . . . . . . . . . . . 15–7
15.4.4 Selection of Data Types (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–8
15.5 Choices in Procedure Division Statements . . . . . . . . . . . . . . . . . . . . . . . . . 15–8
15.5.1 Using GO TO DEPENDING ON Instead of IF, GO TO . . . . . . . . . . . . 15–8
15.5.2 Using Indexing Instead of Subscripting . . . . . . . . . . . . . . . . . . . . . . . . 15–9
15.5.3 Using SEARCH ALL Instead of SEARCH . . . . . . . . . . . . . . . . . . . . . . 15–9
15.5.4 Selecting Hypersort for Sorting Tasks . . . . . . . . . . . . . . . . . . . . . . . . . 15–9
15.5.5 Minimizing USE Procedures with LINKAGE SECTION References
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–10
15.6 I/O Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–10
15.6.1 Using the APPLY Clause . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–10
15.6.1.1 Using the PREALLOCATION Phrase of the APPLY Clause . . . . . 15–10
15.6.1.2 Using the EXTENSION Phrase of the APPLY Clause . . . . . . . . . . 15–11
15.6.1.3 Using the DEFERRED-WRITE Phrase of the APPLY Clause . . . . 15–11
15.6.1.4 Using the FILL-SIZE ON Phrase of the APPLY Clause . . . . . . . . . 15–12
15.6.1.5 Using the WINDOW Phrase of the APPLY Clause . . . . . . . . . . . . . 15–12
15.6.2 Using Multiple Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–12
15.6.3 Sharing Record Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–13
15.6.4 Using COMP Unsigned Longword Integers . . . . . . . . . . . . . . . . . . . . . 15–15
15.7 Optimizing File Design (OpenVMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–15
15.7.1 Sequential Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–15
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