Preface

The Purpose of This Manual

The VOS Tape Processing User's Guide and Programmer's Reference (R052) documents the use of the VOS tape processing commands, and the structures, s$ subroutines, opcodes, and tape label information needed to write tape processing programs.

Audience

This manual is intended for users of the VOS tape processing facility, including programmers who are working with applications that read or write tapes.

Before using the VOS Tape Processing User's Guide and Programmer's Reference (R052), you should be familiar with the VOS Commands Reference Manual . Before using the programmer's reference section in particular, you should be familiar with the VOS Subroutines Manuals.

Revision Information

This is Addendum A. For information on which release of the software this manual documents, see the Notice page.

Change bars, which appear in the margin, note the specific changes to text. Note, however, that change bars are not used in new chapters or appendixes.

This update package incorporates the following changes.

Manual Organization

This manual is divided into two parts. The first part is a user's guide that explains how to process tapes from command level. The second part is a programmer's reference that explains how to process tapes from within a program.

Chapter 1, "Overview," describes how to use tapes under VOS. It briefly outlines the steps to follow and the choices to make when processing a tape.

Part 1, "VOS Tape Processing User's Guide," contains 13 chapters.

Chapter 2, "Inserting and Loading a Tape," explains how to physically load a tape onto a Stratus-provided tape drive.

Chapter 3, "Attaching a Port," explains how to explicitly and implicitly attach a VOS port to a tape drive.

Chapter 4, "Setting the Tape Drive Parameters," explains how to use the set_tape_drive_params command.

Chapter 5, "Mounting a Tape," explains how to mount a tape for reading or writing and how to create a new tape volume.

Chapter 6, "Listing a Tape," explains how to list the contents of a tape or a save tape.

Chapter 7, "Reading Data from Tape to Disk," explains how to read an entire tape or particular files on a tape with the read_tape command. It explains how to read labeled tapes and unlabeled tapes, and tells you how to process tapes with labels VOS cannot interpret. It also explains how to position a tape.

Chapter 8, "Writing Data from Disk to Tape," explains how to write a tape.

Chapter 9, "Examining Current Tape Parameters," describes the output of the display_tape_params command.

Chapter 10, "Using Tapes for Logical Backup," describes the use of the save, save_object, restore, and restore_object commands.

Chapter 11, "The dump_tape Command," summarizes the use of the dump_tape command.

Chapter 12, "Copying Entire Tapes," explains how to use the copy_tape commands.

Chapter 13, "Writing to Multiple Tapes," explains how to use the set_second_tape command.

Chapter 14, "Dismounting a Tape and Detaching a Port," describes how to explicitly and implicitly dismount a tape and detach a port.

Part 2, "VOS Tape Programmer's Guide," contains 5 chapters.

Chapter 15, "Procedures for Reading and Writing a Tape with a Program," summarizes the procedures for reading and writing tape files with a program.

Chapter 16, "Attaching a Port to a Tape Drive," describes the use of the s$get_port_id and s$detach_port subroutines.

Chapter 17, "Tape Control Operations," describes the use of the s$control tape processing opcodes, and the tape_drive, tape_mount, and tape_file structures.

Chapter 18, "Input and Output," describes how to open, read, write, and close a tape file with a program.

Chapter 19, "Error Codes Returned During Tape Processing," lists and describes the error codes returned during tape processing.

This manual also has 15 appendixes.

Appendix A, "Tape Label and Header Formats," describes the ANSI, IBM^® OS/VS, and IBM MVS tape labels, and the UNIX tar and cpio header formats.

Appendix B, "Use of the Tape Parameters Structures in BASIC," shows the tape_drive, tape_mount, and tape_file structures in BASIC.

Appendix C, "Use of the Tape Parameters Structures in C," shows the tape_drive, tape_mount, and tape_file structures in C.

Appendix D, "Use of the Tape Parameters Structures in COBOL," shows the tape_drive, tape_mount, and tape_file structures in COBOL.

Appendix E, "Use of the Tape Parameters Structures in FORTRAN," shows the tape_drive, tape_mount, and tape_file structures in FORTRAN.

Appendix F, "Use of the Tape Parameters Structures in Pascal," shows the tape_drive, tape_mount, and tape_file structures in Pascal.

Appendix G, "Sample Programs," provides sample programs for reading a tape, writing ANSI files, writing UNIX files, and a macro for reading an IBM-labeled tape.

Appendix H, "Estimating the Number of Blocks on a Tape," provides methodologies for approximating the amount of data you can store on reel and -inch cartridge tapes.

Appendix I, "Improving Tape Performance," describes seven ways of improving tape processing performance.

Appendix J, "Tape Drive Preventive Maintenance", describing the cleaning procedures for all Stratus-provided tape drives, has been eliminated. Users should now refer to Tape User's Preventive Maintenance Guide  for information on tape head cleaning.

Appendix K, "Troubleshooting Tape Drives," describes how to troubleshoot basic problems on all Stratus-provided tape drives.

Appendix L, "Release 10 and Release 11 Tape Processing: A Comparison," lists the tape processing commands new or changed for Release 11, and shows which arguments have been added or changed. Changes to the open_type argument are also described.

Appendix M, "The Tape Info Structure," describes the still-supported argument structure used by the Release 10 and earlier tape interfaces.

Appendix N, "The System-Operator Subsystem," briefly describes the system-operator subsystem.

Appendix O, "Restoring Corrupted Release 10 Save Tapes," outlines a method for restoring corrupted Release 10 save tapes.

Notation

Stratus documentation uses italics to introduce or define new terms. For example:

Each reel comes with a plastic ring, called the write ring, that can be inserted in the slot around the hub.

Computer font is used to represent text that would appear on your display screen or on a printer. (Such text is referred to as literal text.) For example:

Enter the command list_devices -type tape to determine the name of the tape drive you plan to use.

Slanted font is used to represent general terms that are to be replaced by literal values. In the following example, the user must supply an actual value to replace the slanted font term.

If you want the file to be read to a specific disk file, you can use the file_names option.

Boldface is used to emphasize words within the text. For example:

If you are reading an unlabeled tape, you must specify this argument.

Related Manuals

Refer to the following Stratus manuals for related documentation.

Online Documentation

You can find additional information by viewing the system's online documentation in >system>doc. The online documentation contains the latest information available, including updates and corrections to Stratus manuals.

A Note on the Contents of Stratus Manuals

Stratus manuals document all the subroutines and commands of the user interface. Any other commands and subroutines contained in the operating system are intended solely for use by Stratus personnel and are subject to change without warning.

How to Comment on This Manual

You can comment on this manual by using the command comment_on_manual, which is documented in VOS System Administration: Administering and Customizing a System  and VOS Commands Reference Manual . There are two ways you can use this command to send your comments.

Your comments are sent to Stratus over the Remote Service Network. Note that the operating system includes your name with your comments.

Stratus welcomes any corrections and suggestions for improving this manual.