E-raamat: Practical Usage of MVS REXX

1. Introduction.- 1.1 rexx background.- 1.2 rexx characteristics.- 1.3
rexx applications.- 1.4 REXXs future.-
2. REXX Facilities.- 2.1
Introduction.- 2.2 rexx structure.- 2.2.1 Token.- 2.2.2 Literal string.-
2.2.3 Hexadecimal literal string.- 2.2.4 Binary literal string.- 2.2.5
Symbol.- 2.2.6 Numeric symbol.- 2.2.7 Variables.- 2.2.8 Operator.- 2.2.9
Prefix operators.- 2.2.10 Arithmetic operators.- 2.2.11 Abuttal operator.-
2.2.12 Comparative operators.- 2.2.13 Logical operators.- 2.2.14 Implicit
concatenation.- 2.2.15 Other syntax elements.- 2.3 rexx expressions.- 2.3.1
Arithmetic expression.- 2.3.2 Comparative expression.- 2.3.3 Logical
(Boolean) expression.- 2.4 Statements.- 2.5 Invocation of a rexx exec.- 2.6
Comparison with CLISTS.-
3. REXX Processing Elements.- 3.1 Introduction.- 3.2
Statements.- 3.3 Routines.- 3.3.1 Subroutine.- 3.3.2 Procedure.- 3.3.3
Function.- 3.3.4 Search order.- 3.3.5 Invocation.- 3.3.6 Parameters
(arguments).- 3.3.7 Return.- 3.3.8 Communication between execs.- 3.4 Types of
instruction.- 3.4.1 Conditional control.- 3.4.2 Loop control.- 3.5 Control
processing flow.- 3.6 Assignment.- 3.7 Stack (queue) processing.- 3.7.1 Stack
as terminal input buffer.- 3.7.2 Stack used for general data storage.- 3.7.3
Stack used for passing data between execs.- 3.7.4 File buffer.- 3.8 Parsing.-
3.9 Debugging.- 3.10 Miscellaneous instructions.- 3.11 Commands.- 3.12
Special variables.- 3.12.1 rc Return code.- 3.12.2 result Function
result.- 3.12.3 sigl Source line number.-
4. REXX Instructions.- 4.1
Introduction.- 4.2 Instruction descriptions.- 4.2.1 address Set
environment.- 4.2.2 arg Fetch argument.- 4.2.3 call Invoke routine.-
4.2.4 do Define start of DO-block.- 4.2.5 drop Free variable.- 4.2.6
exit- Terminate exec.- 4.2.7 if Conditional execution.- 4.2.8 interpret
Interpret statement.- 4.2.9 iterate Terminate the current cycle in the
Do-loop.- 4.2.10 leave Terminate Do-loop.- 4.2.11 nop No-operation.-
4.2.12 numeri c Define numeric formats.- 4.2.13 options Pass special
parameters to the language processor.- 4.2.14 parse Assign data.- 4.2.15
procedure Define internal procedure.- 4.2.16 pull Fetch data element from
the head of the stack.- 4.2.17 push Set data element at the head of the
stack.- 4.2.18 queue Set data element at the tail of the stack.- 4.2.19
return Return from routine.- 4.2.20 say Display.- 4.2.21 select Select
one condition from a series of conditions.- 4.2.22 signal Enable (or
disable) an exception condition, or cause control to be passed to a routine
(or label).- 4.2.23 trace Set debugging options.- 4.2.24 upper Transform
lowercase characters into uppercase.- 4.2.25 = - Assign.- 4.2.26 Command.-
4.3 Examples.-
5. Exception Handling.- 5.1 Introduction.- 5.2 Condition
traps.- 5.2.1 error condition.- 5.2.2 failure condition.- 5.2.3 halt
condition.- 5.2.4 novalue condition.- 5.2.5 syntax condition.- 5.2.6 Stacked
conditions.- 5.3 Explicit invocation.-
6. String Processing.- 6.1
Introduction.- 6.2 Word parsing.- 6.3 Delimiter parsing.- 6.4 Positional
parsing.- 6.5 Dynamic parsing.- 6.6 Argument parsing.- 6.7 Worked examples.-
7. Numbers and Arithmetic.- 7.1 Introduction.- 7.2 Number.- 7.3 Arithmetic
operators.- 7.3.1 Power (exponentiation).- 7.3.2 Multiplication.- 7.3.3
Division.- 7.3.4 Modulo (integer) division.- 7.3.5 Remainder division.- 7.3.6
Numeric comparison.- 7.4 Precision and representation.- 7.4.1 Computational
base.- 7.4.2 Retention of significance.- 7.4.3 Arithmetic exceptions.- 7.5
Sequence of operations.- 7.6 Numeric formatting.-
8. Input/Output.- 8.1
Introduction.- 8.2 Data buffering.- 8.3 Opening and closing the data files.-
8.4 Terminal operations.- 8.5 File-mode operations.- 8.5.1 File positioning.-
8.5.2 Write operation.- 8.5.3 Delete data operation.- 8.5.4 Read operation.-
8.5.5 Update operation.-
9. Debugging.- 9.1 Introduction.- 9.2 Exception
conditions.- 9.3 Tracing options.- 9.3.1 all Display all expressions before
execution.- 9.3.2 commands Display all conmiands before execution.- 9.3.3
error Display all commands which return an error condition.- 9.3.4 failure
Display all commands which return a negative error condition.- 9.3.5
intermediate Display all expressions (with intermediate results) before
being executed.- 9.3.6 labels Display all labels as they are reached.-
9.3.7 results Display all expressions (with end results) before being
executed.- 9.3.8 syntax Check syntax without processing the statements.-
9.3.9 n Suppress trace intervention.- 9.4 Trace output.- 9.4.1 Trace data
prefixes.- 9.4.2 Trace intermediate data prefixes.- 9.4.3 Trace output
example.- 9.5 Interactive debug.- 9.5.1 Interactive debugging example.- 9.6
Parametric debug.- 9.7 Errors with host commands and functions.-
10. REXX
Built-in Functions.- 10.1 Introduction.- 10.1.1 Function-like (direct)
invocation.- 10.1.2 Call invocation.- 10.1.3 Internal functions.- 10.1.4
Function side-effects.- 10.1.5 Invocation errors.- 10.1.6 Internal data
format.- 10.2 Function definitions.- 10.2.1 abbrev Test whether string is
an abbreviation.- 10.2.2 abs Return absolute value.- 10.2.3 address
Return name of current environment.- 10.2.4 arg Return argument.- 10.2.5
bitand Logical And.- 10.2.6 bitor Logical Or.- 10.2.7 bitxor Logical
Exclusive-Or.- 10.2.8 B2X Convert binary data to hexadecimal.- 10.2.9
centre (CENTER) Centralise data.- 10.2.10 compare Compare.- 10.2.11
condition Return condition.- 10.2.12 copies Duplicate data.- 10.2.13 C2D
Convert character data to decimal.- 10.2.14 C2X Convert character data to
hexadecimal.- 10.2.15 datatype Determine data type.- 10.2.16 date Return
current date.- 10.2.17 delstr Delete substring.- 10.2.18 delword Delete
words.- 10.2.19 digits Return the numeric DIGITS setting.- 10.2.20 D2C
Convert decimal data to character.- 10.2.21 D2X Convert hexadecimal data to
character.- 10.2.22 errortext Retum message text.- 10.2.23 find Search
for word.- 10.2.24 form Determine numeric FORM setting.- 10.2.25 format
Format numeric value.- 10.2.26 fuzz Determine numeric FUZZ setting.-
10.2.27 index Search for substring.- 10.2.28 insert Insert substring.-
10.2.29 justify Justify string of words.- 10.2.30 lastpos Determine last
position of phrase.- 10.2.31 left Left-align string.- 10.2.32 length
Determine length of string.- 10.2.33 linesize Retum the (maximum) width of
a terminal line.- 10.2.34 max Determine the maximum of a series of numeric
values.- 10.2.35 min Determine the minimum of a series of numeric values.-
10.2.36 overlay Overlay part of a string with a phrase.- 10.2.37 pos
Search for substring.- 10.2.38 queued Determine the number of entries in
the queue.- 10.2.39 random Generate a (pseudo-)random number.- 10.2.40
reverse Reverse the sequence of data.- 10.2.41 right Right-align string.-
10.2.42 sign Determine numeric sign.- 10.2.43 sourceline Retum program
line.- 10.2.44 space Insert fill-character between words.- 10.2.45 strip
Remove padding-characters at the start or end of a string.- 10.2.46 substr
Extract substring.- 10.2.47 suBWORD Extract series of words from
word-string.- 10.2.48 symbol Determine the status of a symbol.- 10.2.49
time Return the current time-of-day.- 10.2.50 trace Return (and set)
current trace mode.- 10.2.51 translate Translate.- 10.2.52 trunc Truncate
numeric value.- 10.2.53 userid Return Userid.- 10.2.54 value Return the
content of a symbol.- 10.2.55 verify Test whether only characters in a
phrase are present in string.- 10.2.56 word Fetch word.- 10.2.57 wordindex
Determine the character position of a word in a string of words.- 10.2.58
wordlength Determine word length.- 10.2.59 wordpos Determine word-number
of word in word-string.- 10.2.60 words Determine number of words in
word-string.- 10.2.61 xrange Define a range of hexadecimal values.- 10.2.62
X2B Convert hexadecimal to binary.- 10.2.63 X2c Convert hexadecimal to
character.- 10.2.64 X2D Convert hexadecimal to decimal.- 10.3 Examples.-
11. Host REXX Commands.- 11.1 Introduction.- 11.2 Host rexx command
definitions.- 11.2.1 delstack Delete stack.- 11.2.2 dropbuf Release
buffer.- 11.2.3 execio Perform input/output operation.- 11.2.4 executil
Specify execution environment for rexx program.- 11.2.5 he Halt execution.-
11.2.6 hi Halt interpretation.- 11.2.7 ht Halt typing.- 11.2.8 makebuf
Create new buffer in the stack.- 11.2.9 newstack Create a new stack.-
11.2.10 qbuf Query buffer.- 11.2.11 qelem Query elements.- 11.2.12 qstack
Query stack.- 11.2.13 rt Resume typing.- 11.2.14 subcom Confirm the
host environment.- 11.2.15 te Trace end.- 11.2.16 ts Trace start.- 11.3
Example.-
12. MVS Command Functions.- 12.1 Introduction.- 12.2 mvs command
function calls.- 12.2.1 getmsg Retrieve a console session message.- 12.2.2
listdsi List (obtain) dataset information.- 12.2.3 msg Set (interrogate)
clist CONTROL msg option.- 12.2.4 outtrap Trap tso display output.- 12.2.5
prompt Set (interrogate) clist CONTROL prompt option.- 12.2.6 setlang Set
language.- 12.2.7 storage Set (interrogate) main storage content.- 12.2.8
sysdsn Request dataset status.- 12.2.9 sysvar Fetch tso system variable.-
12.3 Invocation of other tso commands.- 12.4 Example.-
13. REXX Invocation.-
13.1 Introduction.- 13.2 Invocation from TSO/ISPF.- 13.3 Invocation from
batch TSO.- 13.4 Invocation from MVS.- 13.5 Linkage to the host (MVS-TSO)
environment.- 13.6 Linkage to programs.- 13.6.1 link (ATTACH).- 13.6.2
linkmvs (ATTACHMVS).- 13.6.3 linkpgm (ATTACHPGM).- 13.7 Interface with
ispexec (ISPF Dialog Manager).- 13.8 Interface with i SRED i T (ISPF/PDF Edit
macro).- 13.8.1 Macro example.- 13.9 Interface with DB2 (Database2).- 13.9.1
DB2 invocation example.- 13.10 Interface with qmf (Query Management
Facility).- 13.10.1 dsqcix qmf Callable Interface.- 13.10.2 dsqcci qmf
Command Interface.- 13.11 Interface from programs with REXX.-
14. System
Interfaces.- 14.1 Introduction.- 14.2 General conditions.- 14.2.1 C/370
restrictions.- 14.2.2 Other program language restrictions.- 14.3 Invocation
of a rexx exec.- 14.3.1 Interface from programs to batch rexx (IRXJCL
service).- 14.3.2 Invocation of a rexx exec using the tso Service Facility
(IJKEFTSR service).- 14.4 Interface from programs to rexx processor
(IRXEXEC).- 14.4.1 Sample program.- 14.4.2 Invocation of an in-store exec.-
14.5 Program access to rexx variables (IRXEXCOM service).- 14.5.1 Sample
programs.- 14.5.2 Sample retrieval program.- 14.6 Stack processing (IRXSTK
service).- 14.6.1 Sample programs.- 14.7 Command interface.- 14.7.1 Entry
conditions.- 14.7.2 Parameter list.- 14.7.3 Exit conditions.- 14.7.4
Examples.- 14.7.5 Command registration interface.- 14.7.6 Command router.-
14.8 Function interface.- 14.8.1 Entry conditions.- 14.8.2 Exit conditions.-
14.8.3 Sample function program.- 14.9 Function package.- 14.9.1 Function
directory.- 14.10 Load routine irxload service.- 14.11 Initialisation
routine irxinit service.- 14.11.1 Sample program.- 14.12 Get result
irxrlt service.- 14.12.1 Sample program.- 14.13 Control blocks.- 14.13.1
Argument List.- 14.13.2 efpl (External Function Parameter List).- 14.13.3
envblock (Environment Block).- 14.13.4 evalblock (Evaluation Block).- 14.13.5
execblk (Exec Block).- 14.13.6 instblk (In-storage Control Block).- 14.13.7
shvblock (Shared Variable (Request) Block).- 14.13.8 veep (Vector of External
Entry Points).- 14.14 Examples.- 14.14.1 Assembler implementation.- 14.14.2
C/370 implementation.- 14.14.3 cobol implementation.- 14.14.4 PL/I
implementation.-
15. Worked Examples.- 15.1 Introduction.- 15.2 Worked
example 1.- 15.3 Worked example 2.- 15.4 Worked example 3.- 15.5 Worked
example 4.- 15.6 Worked example 5.- Appendix A. Syntax Notation.- Appendix B.
Glossary.