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Toolkit Feature Interactive Debug Facility User's Guide

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Toolkit Feature Interactive Debug Facility User's Guide High Level Assembler for z/OS & z/VM & z/VSE IBM Toolkit Feature Interactive Debug Facility User's Guide Version 1 Release 6 GC26-8709-09 High Level Assembler for z/OS & z/VM & z/VSE IBM Toolkit Feature Interactive Debug Facility User's Guide Version 1 Release 6 GC26-8709-09 Note Before using this information and the product it supports, be sure to read the general information under “Notices” on page 311. This edition applies to IBM High Level Assembler for z/OS & z/VM & z/VSE Toolkit Feature, Release 6, Program Number 5696-234 and to any subsequent releases until otherwise indicated in new editions. Make sure that you are using the correct edition for the level of the product. Order publications through your IBM representative or the IBM branch office serving your locality. IBM welcomes your comments. For information on how to send comments, see “How to send your comments to IBM” on page xv. © Copyright IBM Corporation 1992, 2017. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Figures ............... ix Building a module on z/OS ........ 17 Building a module on CMS ........ 17 About this book ........... xi Building a phase on z/VSE ........ 17 Running ASMLANGX ........... 18 Syntax notation ............. xi Extraction file allocation on z/OS ...... 18 Online language extraction on TSO ..... 19 How to send your comments to IBM .. xv Batch language extraction on z/OS ..... 19 If you have a technical problem ....... xv Online language extraction on CMS ..... 20 Batch language extraction on z/VSE ..... 20 Summary of changes ........ xvii Which files to keep ........... 21 Return codes .............. 21 Part 1. What is IDF and how do I start using it? ........... 1 Chapter 4. Invoking IDF to debug your program .............. 23 Chapter 1. Introduction to the Interactive Running IDF on TSO and CMS ........ 23 Running IDF via TSO batch job........ 24 Debug Facility ............ 3 Running IDF via z/OS batch job ....... 25 Capabilities ............... 3 Running IDF on z/VSE .......... 26 Execution control ............ 4 IDF options at invocation.......... 27 Symbol support ............ 4 1ADSTOP (CMS only) .......... 27 Typeover storage modification ....... 5 AMODE24 | AMODE31 | AMODE64 (z/OS Intelligent cursor sensing ......... 5 only) ............... 27 Screen swapping ............ 5 ASCII ............... 28 Record and playback .......... 5 AUTOLOAD | NOAUTOLD ....... 28 Customization - profile and macros...... 5 AUTOSIZE | NOAUTOSZ ........ 28 Where can I run IDF? ........... 6 BCX | NOBCX ............ 29 Environments supported ......... 6 CKSUBCM ............. 29 Limitations when debugging on TSO ..... 6 CMDLOG .............. 29 Limitations when debugging on CMS ..... 7 CMPEXIT .............. 29 Limitations when debugging under z/VSE ... 7 COLORS | COLOURS ......... 30 COMMAND ............. 30 Chapter 2. Getting started with IDF ... 9 DMSO (CMS only) ........... 30 Program preparation............ 9 EXITEXEC.............. 31 Program debug basics ........... 9 FASTPATH | PATH | PATHFILE ..... 31 Sample debug session on TSO ........ 10 FULLQUAL ............. 31 Sample program preparation ....... 10 HEXDISP .............. 32 Invoking IDF ............. 10 HEXINPUT ............. 32 Invoking IDF with a TSO batch job ..... 10 IMPMACRO | NOIMPMAC ....... 32 Sample debug session on z/OS ........ 11 INVPSW | NOINVPSW ......... 32 Invoking IDF with a batch job ....... 11 ISA (CMS only) ............ 33 Sample debug session on CMS ........ 11 LIBE (z/OS and CMS).......... 33 Sample program preparation ....... 11 LINE (CMS only) ........... 33 Invoking IDF ............. 11 LUNAME (z/VSE and z/OS) ....... 33 Sample debug session on z/VSE ....... 12 LSMDEBUG ............. 34 Sample program preparation ....... 12 MACROLOG ............. 34 Invoking IDF ............. 12 MODE (CMS only) ........... 34 Running IDF on a sample program ...... 12 MODMAP | NOMODMAP (CMS only) ... 34 NODSECTS ............. 35 Part 2. Guide to using IDF ..... 15 NUCEXT (CMS only) .......... 35 OFFSET .............. 35 OLDBREAK ............. 35 Chapter 3. Using ASMLANGX to extract PASSPGM .............. 36 source-level information ....... 17 PROFILE | NOPROFIL ......... 36 Assembly requirements .......... 17 QWDUMP.............. 36 Program build requirements ......... 17 RISK ............... 36 © Copyright IBM Corp. 1992, 2017 iii RLOG ............... 37 Dynamically loaded programs ........ 59 ROWSTYLE ............. 37 Programs invoked by REXX ......... 60 SBORDER .............. 37 Programs declaring interrupt routines ..... 60 SCDACTIV ............. 37 Causing a break-in event .......... 60 SELFNUCX (CMS only) ......... 38 Your program's defined limits ........ 61 STOPNOP | NOSTOPNP ........ 38 PER versus non-PER mode ......... 61 STOPSTMT | NOSTOPST ........ 38 Programs performing full-screen I/O ...... 62 SVC97 | NOSVC97 (z/OS only) ...... 39 Using a message-trapping tool ........ 63 SWAP ............... 39 SYSTEM (CMS only) .......... 39 Chapter 7. Debugging programs on TRACEALL ............. 39 z/VSE ............... 65 TRANS (CMS only)........... 40 Data set naming conventions ........ 65 UNFTDUMP ............. 40 How to specify parameters for your program ... 65 Initialization of general-purpose registers (GPRs) .. 40 Loading programs ............ 65 Initialization of floating point registers ..... 41 JCL requirements ........... 65 Initialization of access registers ........ 41 Dynamically loaded programs ........ 66 The PATH, FASTPATH, and PATHFILE options .. 41 Running with subtasks .......... 67 Using the PATH option ......... 41 Running with CICS............ 67 Using the PATHFILE option ........ 42 Using ASMIDF to debug a CICS/VSE application 67 Using the FASTPATH option ....... 42 Debugging STXIT code .......... 68 Excluding called subroutines ....... 42 Causing a break-in event .......... 68 Your program's defined limits ........ 69 Chapter 5. Debugging programs on Programs performing full-screen I/O ...... 69 z/OS ................ 43 Data set naming conventions ........ 43 Chapter 8. Windows, PF keys, cursor Optional data set file allocations ....... 43 positioning, and other operational Breakpoint method selection (TSO) ...... 43 details ............... 71 SVC 97 breakpoints........... 44 Invalid opcode breakpoints ........ 44 Windows ............... 71 Specifying the breakpoint method ...... 44 AdStops window (CMS only) ....... 72 Breakpoint method (z/OS batch) ....... 44 Additional Floating-Point Registers window .. 72 How to specify parameters for your program (TSO) 45 Break window ............ 73 The COMMAND option (TSO) ....... 45 Current Registers window ........ 74 How to specify parameters for your program (z/OS Disassembly window .......... 75 Batch) ................ 46 Dump window ............ 77 Loading programs (TSO) .......... 46 Entry Point Names window ........ 79 File allocation requirements ........ 47 LSM Information window ........ 80 The TSOEXEC command ......... 47 Minimized Windows Viewer........ 80 Programs requiring environmental setup (TSO) .. 47 Options window ........... 81 The COMMAND option ......... 48 Old Registers window .......... 82 TSO batch and z/OS batch job requirements ... 48 Skipped Subroutines window ....... 82 Dynamically loaded programs (TSO) ...... 48 Target Status window .......... 83 Programs invoked by REXX (TSO)....... 50 Some examples of actual screens ...... 83 ISPF applications (TSO) .......... 50 Specifying a window ........... 85 DB2 applications (TSO) .......... 50 PF keys................ 86 Causing a break-in event (TSO)........ 51 Command record and playback features ..... 86 Your program's defined limits ........ 51 Address expressions ........... 87 Programs performing full-screen I/O (TSO) ... 52 Addresses displayed by IDF ......... 89 Applications that use z/OS subtasking ..... 52 Arguments and cursor positioning....... 89 Chapter 6. Debugging programs on Chapter 9. Source-level debug CMS ................ 55 additional capabilities ........ 91 Program preparation on CMS ........ 55 Controlling single-stepping your program .... 92 How to specify parameters for your program ... 55 Displaying and changing items ........ 93 User-area programs............ 56 Variable expressions ........... 93 CMS transient programs .......... 56 Variable scope ............ 94 CMS nucleus extensions loaded explicitly .... 56 Variable names ............ 94 Self-loading CMS nucleus extensions ...... 57 Simple variables ............ 94 Programs requiring environmental setup .... 57 Aggregate variables .......... 94 The COMMAND option ......... 57 Dot qualification............ 94 iv HLASM V1R6 Toolkit Feature Interactive Debug Facility User's Guide Based variables ............ 95 GPR ................ 135 Array indexing ............ 95 GPRG (z/OS only) ........... 136 Substrings .............. 95 GPRH (z/OS only) ........... 136 Displaying variable names ......... 96 GSTATUS .............. 136 Displaying CALLERS ........... 96 HIDE ................ 137 Source level support ........... 97 HISTORY............... 138 ICOUNT ............... 139 Chapter 10. Commands and operating KWDSYN .............. 139 procedures ............. 99 LANGUAGE + ............. 139 LANGUAGE COLOR .......... 141 IDF commands cross-reference ........ 99 LANGUAGE COMMENTS ......... 141 ABEND (CMS and z/OS) ......... 104 LANGUAGE DEBUG .......... 142 ADSTOP (CMS only) ........... 104 LANGUAGE DECLARES ......... 142 ADSTOPS (CMS only) .......... 105 LANGUAGE DROP
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