CP Conventions •••••..••••...••••••••••..••••..•••..•...•......••...•.....•..... 276
CP Coding Conventions .......................................................... 276
CP Loadlist Requirements ........................................................ 278
How to Add a Console Function to CP ••.•.••.••••..•••••.•••••..••.•..•••••.•••.•..•• 280 Print Buffers and Forms Control •••••.•••••.•••••••••••••••••.•••••.•••••..••••..••• 281
Adding New Print Buffer Images ................................................... 283 UCS Buffer Images for the 1403 Printer ........................................... 283 UCSB Buffer Images for the 3211 Printer .......................................... 285
FOB Buffer Images for the 3289 Model 4 Printer .................................... 288 UCC Buffer Images for the 3203 Printer .......................................... 289
PIB Buffer Images for the 3262 Model I and II Printers ............................... 2.91 Forms Control Buffer ............................................................ 292
IBM 3800 Printing Subsystem •••••••.•••••••••••••••..•••.•••••.•••••.••••••••.•••• 295 Using the 3800 Printer as a Dedicated Device ......................................... 295 Using the 3800 Printer as a Real Spooling Device ...................................... 295
Specifying Printer Options ...................................................... 296
Creating Control Tables ....................................................... 296
Storing and Loading Control Tables .............................................. 297
Recovering from I/O Errors .................................................... 297
Displaying Printer Control Information ............................................ 297 Using the 3800 Printer as a Virtual Spooling Device .................................... 297
Defining a Virtual 3800 Printer .................................................. 298
Loading the Virtual 3800 and Printing Virtual 3800 Spool Files ......................... 298
Recovering from I/O Errors .................................................... 299
Displaying Control Information ........................ . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Journaling Logon, Autolog, and Link Commands ..••••••••.••••••••••••..••••••..••••••.. 300 Suppressing Passwords Entered on the Command-Line ••••.•••••••••••••.••••..••••••..•.• 301 Part 2. Conversational Monitor System (CMS) .•••••••.••••••••••••.••••••.••••••.••••• 302 Introduction To CMS •••••••••.•.•..••••••••••••••••••••.•••.••..•••••••.•.•.•••. 303 The CMS Command Language ..................................................... 303 The File System ................................................................ 303 Migration from the 800-byte File System to the Extended File System ...................... 304 Migration Considerations ...................................................... 305 Coexistence of VM/SP CMS and Earlier Versions of CMS ............................ 308 Converting CMS Files ......................................................... 309 Program Development ............................................................ 309 ABEND Processing ............................................................. 310 ABEND Exit Routine Processing ................................................ 310 CMS Abend Recovery ......................................................... 311
Interrupt Handling In CMS ••••••.••.••••.•••••••••••••.•••••••••••••.••••••••..••• 312 SVC Interruptions ............................................................... 312
Internal Linkage SVCs ........................................................ 312
Input/Output Interruptions ........................................................ 313
Terminal Interruptions ........................................................... 313
Reader/Punch/Printer Interruptions ................................................ 314
User-Controlled Device Interruptions ................................................ 314
Program Interruptions ............................................................ 314
External Interruptions ............................................................ 314
Machine Check Interruptions ...................................................... 314
Functional InC ormation •••••.••••.••.•••••.•••••••••••••••••••••.•••••••••.••••.••. 315
Register Usage ................................................................. 315
Structure of DMSNUC ........................................................... 315
USERSECT (User Area) ...................................................... 315
DEVTAB (Device Table) ..................................................... 316
Structure of CMS Storage ......................................................... 317
Free Storage Management ........................................................ 323
GETMAIN Free Storage Management ............................................ 323
DMSFREE Free Storage Management ............................................ 324
Contents xix

Releasing Allocated Storage .................................................... 329 DMSFRE Service Routines ..................................................... 330 Error Codes from DMSFREE, DMSFRES, and DMSFRET ............................ 332 CMS Handling of PSW Keys ...................................................... 332
The DMSKEY Macro ......................................................... 333
The DMSEXS Macro ......................................................... 334 CiviS SVC Handling ............................................................. 334 SVC Types and Linkage Conventions ............................................. 335 Search Hierarchy for SVC 202 .................................................. 339 User and Transient Program Areas ............................................... 343
Called Rouq.ne Start-Up Table .................................................. 343
Returning to the Calling Routine ................................................. 344
Dynamic Linkage--Subcom ........................................................ 346
System Product Editor Interface to Access Files in Storage ............................... 348 CMS Interface for Display Terminals ................................................ 350 Using the DASD Block I/O System Service from eMS •.••••••••••••••••••••••••••••••••• 352 eMS IUCV Support ..••••.••..•.•••••••••••.••.••••••••••••••••••••••••••.•••••• 355 HNDIUCV Macro .............................................................. 355 CMSIUCV Macro ................................................................ 359
Exits ......................................................................... 364 Using CMS IUCV to Communicate Between Two Virtual Machines ........................ 365
Guidelines and Limitations of the CMS IUCV Support .................................. 367 OS Macro Simulation Under CMS •••••••••.•••.•.••••..••••••••••••••••••••••••••.. 370 OS Data Management Simulation ................................................... 370 Handling Files that Reside on CMS Disks .......................................... 370 Handling Files that Reside on OS or DOS Disks ..................................... 370 Simulation Notes ............................................................. 372
Access Method Support ........................................................ 379
Reading OS Data Sets and VSE Files Using OS Macros .................................. 383 VSE Support Under eMS ••••••••.•••••••••••••••••••••••••••••••••••••••••••••••• 386
Hardware Devices Supported ...................................................... 387 CMS Support of VSE Functions .................................................... 387
Logical Unit Assignment ....................................................... 389 VSE Supervisor and I/O Macros Supported by CMS/DOS ............................... 391
Supervisor Macros ............................................................ 391
Sequential Access Method --Declarative Macros .................................... 400 Sequential Access Method --Imperative Macros ..................................... 409 VSE Transient Routines .......................................................... 409 EXCP Support in CMS/DOS ...................................................... 410 VSE Supervisor Control Blocks Simulated by CMS/DOS ................................ 411 User Considerations and Responsibilities ............................................. 411 VSE System Generation and Updating Considerations ................................... 411 VM/SP Directory Entries ......................................................... 412
When the VSE System Must Be Online .............................................. 413
Performance ............. ' ...................................................... 413
Execution Considerations and Restrictions ............................................ 413 eMS Support for OS and VSE/VSAM Functions ••••••••••••••••••••••••••••.•••••••••• 415 Hardware Devices Supported .................•.................................... 415 VSE Supervisor Macros and Logical Transients Support for VSAM ......................... 416
Data Set Considerations ............................................... 416 ISAM Interface Program (lIP) ..................................................... 416 Saving the eMS System •••••••••••••••••••••••••••••••••••••••••••••••••••.••••••• 417 Saved System Restrictions for CMS ................................................. 417
The eMS Batch Facility •••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 418
Installing the CMS Batch Machine .................................................. 418
Resetting the CMS Batch Facility System Limits ....................................... 419
Writing Routines To Handle Special Installation Input ................................... 419
BATEXIT1: Processing User-Specified Control Language ............................. 419
BATEXIT2: Processing the Batch Facility /JOB Control Card ......................... 420 EXEC Procedures for the Batch Facility Virtual Machine ................................ 420 Data Security under the Batch Facility ............................................... 420 xx VM/SP System Programmer's Guide