ESS-PFURM-001 · Reference Manual · April 1996

Endless PL/I for POSIX Systems

This manual defines Endless PL/I for POSIX Systems. It includes the keywords and the semantic and syntax rules of PL/I programming language statements, attributes, built-in functions, and other language elements.

Operating System and Version: Linux; macOS; Tru64 UNIX
Software Version: Endless PL/I for POSIX Systems Version 2.0

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Table of Contents

1. Intended Audience
2. Associated Documents
3. Conventions
4. Technical Assumptions
5. Terminological Conventions

1. Program Structure and Content

1.1. Lexical Elements
1.2. Statements
1.3. Program Format
1.4. Blocks
1.5. Data and Variables

2. Declarations

2.1. DECLARE Statement
2.2. Attributes

3. Data Types

3.1. Summary of Data Types
3.2. Arithmetic Data
3.3. Character String Data
3.4. Bit-String Data
3.5. Pointer Data
3.6. Offset Data
3.7. Label Data
3.8. Entry Data
3.9. File Data
3.10. Area Data
3.11. Condition Data

4. Aggregates

4.1. Arrays
4.2. Structures
4.3. Arrays of Structures
4.4. Internal Representation of Aggregate Data

5. Storage Classes

5.1. Automatic Variables
5.2. Static Variables
5.3. Internal Variables
5.4. External Variables
5.5. Based Variables
5.6. Controlled Variables
5.7. Dynamically Allocated Variables
5.8. Defined Variables
5.9. Storage Sharing

6. Expressions and Data Type Conversions

6.1. Assignment Statement
6.2. Operators and Operands
6.3. Precedence of Operators and Expression Evaluation
6.4. Data Type Conversion of Operands and Expressions

7. Procedures

7.1. PROCEDURE Statement
7.2. Functions and Function References
7.3. ENTRY Statement
7.4. CALL Statement
7.5. Parameters and Arguments
7.6. Calling External and Internal Procedures
7.7. Terminating Procedures
7.8. Passing Arguments to Non-PL/I Procedures

8. Program Control

8.1. DO Groups and Statements
8.2. BEGIN Statement
8.3. END Statement
8.4. IF Statement
8.5. SELECT Statement
8.6. GOTO Statement
8.7. LEAVE Statement
8.8. STOP Statement
8.9. Null Statement
8.10. Condition Handling

9. Input and Output

9.1. Opening and Closing Files
9.2. Stream I/O
9.3. Record I/O

10. Preprocessor

10.1. Preprocessor Compilation Control
10.2. Preprocessor Statements
10.3. User-Generated Diagnostic Messages
10.4. Preprocessor Built-In Functions

11. Built-In Functions, Subroutines, and Pseudovariables

11.1. Built-In Function Arguments
11.2. Conditions Signaled
11.3. Summary of Built-In Functions
11.4. Descriptions of Built-In Functions
11.5. Built-In Subroutines
11.6. Pseudovariables

A. Alphabetic Summary of Keywords

B. Dialect Differences

B.1. Data Declarations
B.2. Data Types
B.3. Condition Handling
B.4. Sort Support
B.5. Record and Stream I/O
B.6. Built-in Functions
B.7. Built-in Subroutines

C. Compatibility with PL/I Standards

C.1. Relation to the 1981 PL/I General-Purpose Subset
C.2. 198x PL/I General-Purpose Subset Features Supported
C.3. Full PL/I Features Supported
C.4. Nonstandard Features from Other Implementations
C.5. PL/I-Specific Extensions for POSIX Systems
C.6. Implementation-Defined Values and Features

D. Migration Notes

D.1. Keywords Not Supported
D.2. Differences Between Endless PL/I for POSIX Systems Digital's PL/I and Other Digital-Compatible Versions of PL/I
D.3. Statements
D.4. Data Type Attributes
D.5. Default Values for Data Type Attributes
D.6. Floating Point Data Types
D.7. Scale Factors
D.8. Procedures and Entries Specified with the Returns Option
D.9. Passing Arguments to Non-PL/I Procedures
D.10. GOTO Statement
D.11. Condition Handling
D.12. File Handling
D.13. Preprocessor
D.14. Built-in Functions and Subroutines

E. Language Summary

E.1. Statements
E.2. Attributes
E.3. Statement Format
E.4. Expressions and Data Conversions
E.5. Pseudovariables
E.6. Built-In Subroutines