COBOL Manual for TNS and TNS/R Programs

Contents

HP COBOL Manual for TNS and TNS/R Programs—522555-006

xxii

28. Disk Input and Output (continued)

Types of HP Disk Files 28-9

Unstructured (Sequential) Files 28-9

Structured Files 28-10

Creating and Using HP COBOL Sequential Files 28-14

Entry-Sequenced Files 28-14

Unstructured Files 28-15

EDIT Files 28-16

Creating and Using HP COBOL Relative Files 28-16

Creating and Using HP COBOL Indexed Files 28-17

Creating and Using Queue Files 28-19

Creating a Queue File 28-19

Opening a Queue File 28-19

Reading a Queue File 28-20

Writing to a Queue File 28-20

Establishing Starting Points in Files 28-20

Key of Reference 28-21

Alternate Record Keys 28-22

Positioning 28-23

Repositioning to New Record With Same Alternate Key 28-26

Optimizing Disk File Processing 28-31

Unstructured Files 28-31

Structured Files 28-31

Files With Alternate Keys 28-35

Partitioned Files 28-37

Optimizing Disk File Storage 28-37

Avoiding Deadlock 28-38

Locking and Unlocking Files and Records 28-38

Setting Time Limits on Input-Output Operations 28-39

Using Enscribe and Operating System Routines 28-40

Physical File Names 28-41

Obtaining File Numbers and Other File Attributes 28-41

Determining Whether Two COBOL File Names Specify the Same Physical

File 28-42

Purging a File From an HP COBOL Program 28-43

Purging the Contents of a File From an HP COBOL Program 28-44

Renaming a File From an HP COBOL Program 28-44

Creating a File Having Alternate Keys From an HP COBOL Program 28-45